C4 CORVETTE: Top 5 Problem Areas (And How To Fix Them)

[@RetroCarsForever]

UPDATE- For Common Issue 2 (Pop Up Headlight Motors) I go into more depth in a new video, as I had to make this repair myself. Check it out here- kzbin.info/www/bejne/d2icf6OVnd16sNE

[@alfredposton6281]

Yes - my 92 z-R1 has short in the power seats and auto door lock at same time , Where should we start to look at .

[@FreddieOrtega-cr33p3rofficial]

Just to let you know a company called Torqhead makes an optispark delete kit.

[@JohnJones-dg6lb]

My 91' Corvette when I bought it the right headlight wouldn't pop all the way up but long story short after further inspection it was just getting caught on a wire while flipping up out!

[@RetroCarsForever]

@@JohnJones-dg6lb Whew, easy fix!

[@gregagore8056]

The weatherstripping is a big one. Nearly all C4's that still have their originals will need attention. When looking over a potential C4 purchase be sure to look under the floormats for wet carpeting and check the seat tracks for rust. Both are a sure sign of leaking weatherstripping. Check under the car for major oil leaks too. The most common mistake 1st time buyers make is seriously underestimating repair and replacement parts costs.

[@RetroCarsForever]

Great tips, absolutely agree. Thanks for the comment!

[@Akac3sh]

great advice thank you

[@yomuno2511]

I purchased my 1995 new, and within 3 years the dealership replaced it under warranty. 25 years later, it needs replacing again.

[@allcownoboy]

My Grandpa has one in his garage, and I haven't seen it run in years. I was considering to try to fix it up in order to cheer him up.

[@RetroCarsForever]

A noble cause. Good luck!

[@elithomas8022]

Do it!

[@Swarm509]

Do it man! Probably will give it to you if you do, and can work on it with him.

[@eddiea1213]

Make sure he can still get in and out of it. Not a car for old men.

[@JohnPitts-x2h]

Just bought my C4 Corvette in May. 24 thousand miles on it. And having a great time with my Corvette. Thanks for the heads up.

[@RetroCarsForever]

Enjoy the ride!

[@mokane86]

So how is that vette running now? Are you able to enjoy it this summer? Did you garage it over winter?

[@SaleProofCarReviews]

Problem number 6: Single women don’t like them but married women do..

[@RetroCarsForever]

LOL! Seems to be the case, as we've proven with SCIENCE

[@SaleProofCarReviews]

@@RetroCarsForever although my wife doesn’t like the C4 for some of the same reasons the singles didn’t like it. So much for bringing new balance and Levi Strauss denim shorts back into style

[@craigsbuyer2270]

@@SaleProofCarReviews Lol, don’t know about that had plenty of single ladies really like the look of my white on red ‘93.... so yeah vettes are cool

[@SaleProofCarReviews]

@@craigsbuyer2270 they are cool, but who am I to say? I own a Yugo and am clearly not cool

[@craigsbuyer2270]

@@SaleProofCarReviews Cool is a state of mind, Lol....take care

[@keithpetrocik9265]

Usually 86 and later headlights banging can be caught and fixed for $5. The bushings go out first which can be bought at any auto store. They are Ford window regulator bushings and are in the HELP section. Done many of them!

[@RetroCarsForever]

Yep, about to do mine!

[@CatEye-Cowboy]

Excellent Work!!! My wife and I have dreamed of a C3 Stingray our whole married life together of 30 years this year and always put down the C4. Our son, a senior in high school, managed to get a 1984 Corvette that is in great shape. Not perfect but great and I am now completely sold on the C4. So please continue with the videos on the C4. I plan on getting a couple or three, now that I realize the bargain they are.

[@RetroCarsForever]

Thank you! Agreed that C4s are great bargains right now.

[@lashlarue2266]

Lyle from C & S Corvettes has many videos. He believes the 1991 C4 is the sweet spot C4 year, because of advancements from earlier models, and year before Optispark.

[@stevew8722]

l have 5. And 2 are special editions. A '93 Ruby Red 40th coupe and a '96 CE convertible. Have about 26K in the whole group.

[@joehollahan2431]

Just bought my first C-4 n I thank you for sharing your knowledge! I was just about to take her to a car wash to clean the outside n underbelly, and I didn't know the underbelly wasn't a good idea. Thanks again!!

[@RetroCarsForever]

Glad to help! Now keep in mind if you have a pre-1992 C4 you wont have an Opti so it should be safe. But if you do, beware! Glad I could warn you and hopefully save you some headaches.

[@rayopezzo4052]

Very informative and useful! Note: when disassembling gauge cluster the plastic framework is extremely brittle and fragile on 1988.

[@RetroCarsForever]

Absolutely. Even on my 1996 the interior trim is very brittle and fragile. Had to remove a few pieces and it was stressssful!

[@LvLdGhost]

35 year old plastic is brittle you say? Wow who could of guessed.

[@stevenbunch2855]

I own an '89 automatic corvette, and I love it! First car purchase (not first car however) and it has been super reliable! The only issue I ever had was a bad battery when I bought it; since then, perfection! If you are looking to buy one, spend time waiting for the right one to come into your life (soo many of them out there!). Pro-tip: C4 forums are super friendly and helpful

[@RetroCarsForever]

Congrats! And agreed.

[@gregoryspicer1555]

November 2024. Very well done and helpful, Brad. Much better than the many "5 things I hate about my C4" vids. Your suggestions are 100%. correct The C4 is the perfect car! Thanks.

[@RetroCarsForever]

Thank you, glad you enjoyed it!

[@icelordotis]

Love your videos! They’re so well made, and super helpful as someone looking to get a c4 myself. Keep up the great work man 👍

[@RetroCarsForever]

Thanks so much! Best of luck with your C4 search. Feel free to send me a message or comment if you need any other advice, always glad to help.

[@icelordotis]

@@RetroCarsForever Appreciate it!

[@Skysmeller1]

IceLordOtis ... do it! Their awesome

[@TheEdgerox]

My sentiments exactly! I just bought a 96 C4 - same color as yours and I'm having fun watching your feed. Hope you're doing well sir :)

[@solmermelstein1156]

@@RetroCarsForever 0

[@Skysmeller1]

This was a great video, I’ve had my 87 for a few months now and from your video learned my tires have decent tread but are from 2012! I’ve gone fast on the highway and after seeing that I think my safest bet is to go ahead and get new tires.

[@RetroCarsForever]

Happy to help! Yeah if they're from 2012 that means it's time.

[@tazaxx21]

Thanks for all the C4 videos. I've been wanting one, and I've known they were undervalued for some time.. One point you overlooked when buying a "classic" is any factory rubber bushings will need to be replaced. They get worn and dry rotted just like the tires. I bought a 95 T-bird with 53k mi. for $2300, and I replaced all the front end bushings and control arms/ball joints.. It now rides and drives like a brand new car..

[@stevekeithley8409]

After watching your video, I thought I should drive my 1996 coupe (roof OFF) with 6 speed transmission. Such a great car. Just 41,000 miles. Great handling 330 hp. It makes my 2003 Convertible Corvette feel big and cumbersome. I had been having some starting problems. Checked negative pole cable, it was loose. Tighten it and drove 13.5 miles. Bought new in 1996. Oh, and it's torch red.

[@RetroCarsForever]

Glad I could inspire a drive!

[@RT22-pb2pp]

41,000 miles better sell now before engine needs over haul LOL

[@x1tekja]

Absolutely appreciated that you started with tires. On any older car it has the potential to be the best upgrade you could possibly get for the least amount of time and money.

[@RetroCarsForever]

Thank you, and agreed! It's SO often overlooked, and a safety issue, that I just had to put as Number 1 thing to watch out for.

[@damanisin377]

Well I just joined the C4 community, 1985 manual...cant take the grin off my face. Really impressive vids, simple descriptive and helpful.

[@RetroCarsForever]

Thanks, and congrats!

[@donleblanc7223]

Great video, very informative. I had a '94 that the distributor got fried because of a wiring loom that came loose, and a spark plug wire contacted a hot heat shield, sending a electrical surge back to the distributor, killing it. 2 grand to repair at dealer.

[@RetroCarsForever]

Thanks! And yikes. If it makes ya feel any better, it's likely a lot of the stuff you replaced would need to replaced at some point soon anyhow, and that's not an awful price for all that work, esp from a dealer.

[@TmonkeyWins]

I love mine, it’s a great feeling ride. After I bought mine I noticed a slight bog when punching it, did a full refill (of 20 gallons!) and used a Lucas fuel system cleaner and it ran good as new ever since

[@DanOnFire]

Brad, GREAT VIDEO! Where was this when I first bought my C4?! My ‘96 LT4 has had these problems, and you nailed it. I’m facing the headlight clu-clu-clu-clu-clunk, my weatherstripping was bad and I used an Amazon kit (big mistake), Bose stereo died, and my opti has the slight oil leak. Thanks for showing the websites for buying replacement parts. Lastly, your 96CE is absolutely immaculate. Keep rockin it!!

[@RetroCarsForever]

Thanks so much! Yeah I really wanted to make this video to help with anyone interested in looking at these cars to hopefully avoid headaches. Better late than never! And yes, I wanted to SHOW visually what's up with these things, and the websites, vs just having me blabber on and not showing people the issues.

[@tduncan8118]

I just replaced my weatherstrips with the amazon kit and they are still leaking, did you find any better ones?

[@DanOnFire]

@@tduncan8118 I’m getting ready to purchase a set from Ecklers. Just need to figure out which one they recommend.

[@yahoojedi007]

I just inherited my dad's 91 C4 and he must have also found this video because he managed to fix problems 1 and 2 and had purchased the weather stripping that I just replaced. Now to fix the electrical issues so I can have her running again :)

[@RetroCarsForever]

Best of luck with getting your dad's C4 going again! Glad to hear it's staying in the family.

[@danielreigada1542]

Great video! I have a 1994 Corvette and have had several of these issues mentioned. I have a couple of additional common issues, both of which are not yet fixed on my car: 1) Power antenna does not fully retract. As a result I cannot take it though any automatic car washes, which I should not be doing anyway. 2) Drivers side door interior plastic is loose. Makes it kind of a pain to get a good solid close on that door.

[@RetroCarsForever]

Good ones. If this was a Top 10 list those would def be on the list. Interior trim is pretty brittle on these cars.

[@stewartgregory3364]

1 thing that should be mentioned is that if you over cook a C4 in a turn the rear end will break loose mostly with out warning. Depending on how fast your going is how many revolutions it will make.

[@RetroCarsForever]

Not really a mechanical issue, but I did mention the tricky handling in my “Corvette As First Car Video” here- kzbin.info/www/bejne/mqqpZph-hctoqdk I don’t think these cars are horribly prone to oversteer, they’re just not for beginners. Once I figured out the handling I’ve found it really enjoyable to drive fast.

[@stewartgregory3364]

I agree. Just something to be aware of for 1st time buyers. I only had that happen twice on the street. 1st time in a customers car(oops) when I worked for Chevy. second time I passed someone just where the road narrowed down then went into a sharp turn. Did it several times Auto crossing it(that shouldn't count). Had the front end wash out 1 time. Quick flick of the wheel brought it back under control.

[@RetroCarsForever]

Oh yeah, the handling can catch you off guard if you're not used to it!

[@ugh_adam]

So good! Making me regret not looking harder at C4s before my last vehicle purchase. Also, the shot across Porsche's bow you snuck in there was good for a legitimate LOL from me!

[@RetroCarsForever]

Thanks Adam! Couldn't help myself with the Porsche quip...Now that I'm a Corvette owner, Porsches are suddenly MORTAL enemies! Seriously, I WAS thinking of buying one of those water-cooled Porsches, then I read up on the five common things those things have that can all grenade their engines, and I was like...think I'll stick to good ol' Chevy. See you in a few days, happy to show you my C4 if you're ever curious to get one down the line. They're GREAT cars if you're into the rad era.

[@GammaRay16]

#IMSbearing

[@JamesCulcleasure]

I purchased my first C4 last August. It's a 1996 Competition Yellow LT1 with currently 58 K. My roof panel glass cracked and some weather stripping has deteriorated. Optispark and water pump replaced at the same time, upper radiator hose replaced, lower hose will be replaced soon, new plugs and wires. Replacing the temperature sensor in a few days. Left rear speaker not working so I will check it out. Cassette player stopped working. All in all the car runs FANTASTIC!!! No major issues. Doing an oil change, radiator and brake flush soon. Love to hear some more tips. THANKS.

[@RetroCarsForever]

@@JamesCulcleasure sounds like typical C4 issues for a car that needs attention, glad to hear you’re giving it proper care! Not much tips I can give you that aren’t already in my videos on my channel. But if you weren’t aware, you can buy a new aftermarket targa top for no too much money, as it’s pretty much impossible to fix the crack.

[@jamesculcleasure5011]

I thought about doing a targa top but decided to get one from Melrose T-Tops. I'm also interested in one from a seller on another site.

[@JamesJones-xb8bx]

It’s rare to have to replace the optispark distributor as cleaning it is pretty easy. It’s a simple photo cell with viewing holes in a disc that tells the computer the position of timing and sends spark to the appropriate cylinder. It’s very simple to repair. An electric water pump deletes the seal on the shaft that drives it which eliminates a second source of leak at timing chain cover aside from the pump it self. Using heat shrink at all wire connections on the optispark it self will also greatly reduce moisture and fluids infiltration. Most models have venting at base of the optispark distributor so sealing the wire connections is fine and will protect it. Side note; electric water pump increases Hp. Not by much but it’s cheaper than most modifications especially considering your changing the pump anyway.

[@RetroCarsForever]

Good points, thanks for sharing!

[@HectorGarcia-eo1lq]

I recently got a 94 c4 and all the information I found is very useful to know more about these cars since in the past I had an 81 and it is not the same. Thank you for making this video and for being clear and specific in every detail. It's definitely a big help.

[@RetroCarsForever]

Glad this helped, thank you! Enjoy your 1994.

[@jeremydow-dd2ko]

Good stuff! Love the “members only” jacket! 🤣 Worth mentioning that the LT1 does run a little hotter than most are used to. A 180 degree thermostat will help quite a bit. Very inexpensive and simple to swap out 👍🏻

[@RetroCarsForever]

Thanks...I love that jacket, I wear it every week! As for the 180 degree thermostat, I get that its a popular mod but i'm not certain its needed. If the car is DESIGNED to run way hotter why not just leave it that way? Ive heard arguments that it was designed to run hot to help with emissions and that potentially that ruins longevity but I'm not sure how much of that I believe.

[@LisaNewell-te2ut]

1993 six speed 47,000 option went bad . replaced opti water pump all hoses and spark plugs and wires . running great. great video

[@DUNEATV]

I worked at Van Chevrolet from 1992 to 1996 as a Recon Manager. To me the last real Corvette was the C4!

[@cvette95]

Also experienced the headlights motor issue, fixed myself, and driver seat issue another issue needs attention. Thanks again

[@johnmichael212009]

Best C4 corvette videos period on you tube !!! I hope there are more retro cars to come !! Would love to see some retro Ferrari review videos .

[@RetroCarsForever]

Thank you! I'd LOOOOOVE to review a retro Ferrari. Maybe I'll see who I know who owns one...

[@alexl9334]

Testarossa comes to mind

[@nikkoalpha2]

Super advice on the tires. Last four Corvettes I purchased where at least 14 years and older. All had old and worn tires. Never understood why an owner of a great car would be cheap with tires. I recommend to anyone thinking of buying a C4 Corvette to factor in tires as an immediate maintenance update. Also, original size tires for many C4’s are getting difficult to find and many have very few choices. Great values if one does their homework.

[@RetroCarsForever]

Thanks, and agreed. I was shocked at how many Corvettes had ancient tires on them when I was looking for mine...I think most owners just look at how much tread there is and dont even think about the age! Even the car I bought had 15 year old tires. First thing I did upon purchase was swap them out for new ones. And yes, tire choices are limited these days.

[@craigt5906]

I just fixed my 1996 driver headlight motor that still worked but was making noise total cost was $16 for a new gear which it didn’t really need and the 3 bushings which it definitely needed as tgey were all ground to dust

[@RetroCarsForever]

Nice! Glad it was a cheap and easy fix.

[@thomasmoje5926]

I have a C-4 convertible, circa 1992. So glad I found this video. Headlight on the passenger side is exhibiting the exact symptoms as shown in this video: clunking noises while operating to on/retracted position and I've noticed the white powdery granules collecting below the headlight assembly. So thanks to this video I now know what's entailed at getting that fixed. Other minor issues are the power antenna retractor no longer operates (it's stuck in the half-way up position), the ride adjustment doesn't operate (stuck in the 'touring' setting), and the seat adjustments don't work aside from forward/back and height. All relatively minor glitches due to age that I can get fixed on a car that otherwise is a joy to own and drive.

[@RetroCarsForever]

Glad to help! Best of luck with those other fixes, if this was a Top 10 list of common issues those would’ve made the list too, pretty common and not too terrible to deal with from what I understand.

[@thomasmoje5926]

@Jeff Spicolli I found that I don't really care about the 'sports seat' bladders not operating..the seats are perfectly comfortable the way they are and fit me well; so just forward/backward/height adjustment is fine. Don't care that the power antenna retractor doesn't operate either as long as the radio still works, which it does. I would keep the ride control set on 'touring' anyway so the non-functioning ride control isn't an issue either. My C4 is stuck in the garage now there is an issue with the starter..suspect a sticking solenoid. It's going into the shop soon to find out what's wrong and get that fixed. For the price I paid for it I don't mind putting a little money into it..it's got less than 70,000 miles on it still looks great. I suppose if I wanted to get it back to 'showroom new' condition I'd get those little things corrected but for now providing I get the starter fixed she's good just the way she is. Mine's in the 'bright aqua metallic' color not real common in my area I've only seen one other example in that color in my area.

[@wackysamurai1583]

Got myself a PRISTINE 92 convertible corvette with 95k miles and the thing is AMAZING

[@RetroCarsForever]

Congrats! Enjoy it.

[@davidloyd7442]

I have a pristine White C4 with the white targa top and I love it! Unfortunately my brother went through a series of back and neck operations which cause the car to sit in his garage for 10 years. After a detail and some engine and transmission work it's in A1 condition. Flawless body and paint! I recommend this car. If you really want to enjoy the take off speed, turn off the traction control! Great job on the video!

[@RetroCarsForever]

Thanks, glad you’re still driving yours!

[@767stick]

Great video! After owning 4 C-4's, I can attest to your findings. I had a 93 that had the exact problem with the opti-spark you mentioned. My favorite C-4 was an 89 manual. Had the new Trimec and the L-98 was a problem free runner. I had an 86 4+3 manual Z-51 that I loved but the Trimec was better. My biggest problem with early C-4's was oxygen sensors. I can't explain it but the pre 92 C-4's with the L-98's seemed to be faster and more nimble vettes. Anyone looking to buy a nice C-4 will have a blast ... great cars for the money!

[@RetroCarsForever]

Thanks! 1989 is a really cool "crossover" year for the C4, some of the cool old stuff like the digital dash but you had the the 6 speed (agreed it's way better than the 4 plus 3 in about every way). L98's are a bit gutsier right off the line vs the LT1s, that might be why you found them more nimble. L98s just run out of steam in the upper rev ranges.

[@juliancoletti4073]

@@RetroCarsForever I'm probably a bit late, but I respectfully disagree with the 4+3 vs ZF6. I know I'm probably in the minority here but I think most of the bad rep the 4+3 got came from people who just didn't take the time to understand their principle nor maintain them. The 4+3 is basically a Super T10 4 speed manual with a 2 speed Powerglide bolted behind it. The Super T10 is a "race/sports" oriented gearbox so pretty much bulletproof and the Powerglide is a 70 years old proven design still used for drag racing, so bulletproof as well. Let's not forget that the Sledgehammer C4 kept the original 4+3 gearbox and put a hellish twin turbo 800hp monster in front of it, it this simple gearbox managed to transfer that power all the way to 254mph as well as drive the 3000miles round trip to the test track ( a street car speed record that held for 20 years). There is something deliciously anachronistic about the C4. It's at the middle of this transition from muscle car to sports car. As such it has quirks from both era. It is an incredibly advanced car (first mass produced car to have factory ABS brakes in the world, highest skidpad score on street tires in the world humiliating the Europeans and their fancy handmade sports cars with no radio or AC) while also being the last of a past era with not a single driving aid in sight, an inefficient paperweight of an engine, basically an unpractical, not even that fast relic of another era. And thats what makes the 4+3 so desirable in mind. It's the last corvette with the historical American classic combo, a big displacement V8 bolted to a slow but decisive, linkage rods operated 4 speed. It's one of those things that became innately associated with muscle. It's what Steve McQueen bangs in his Bullit mustang. It's just one of those things you know. Since a lot of the appeal for C4 nowadays comes from the fact that they are accessible while still being old and quirky. Having more quirks ( like the 4+3) is I think good. Also once you get used to it, the 4 speed is lightning fast and strong as hell. It's the kind of tranny that rewards practice. The kind you hate at first and start to love when you realize this thing can be a race gearbox if you use it properly. There is no better feeling than making that perfect 3rd to 2nd downshift on a 4+3. I found the ZF6 to be too mundane and boring. Fine on a BMW autobahn cruiser, but I think a Vette deserves something a bit more "spicy". Hope my rant wasn't too boring

[@RetroCarsForever]

@@juliancoletti4073 Appreciate your thoughts! I'll admit I haven't driven 4 plus 3's for more than a few miles at a time, so perhaps they are another weird C4 quirk that an owner could learn to appreciate over the years.

[@jeffn2166]

Owned a 96 LT4 for 2 years with ZERO problems. Sold it for more than I bought it for when I moved overseas. Would love to get another but they are older now! Oh, so am I. Damn!

[@PhilipMondello]

Really well done, Sir. You could take on Doug DeMuro if you applied this formula to all the collectible cars out there we lust over.

[@RetroCarsForever]

Thanks man! Although I do think it helps to OWN a vehicle, and be deeply involved in the ownership community, to REALLY get this deep of an understanding of what goes wrong with a certain car, and how to fix the issues.

[@PhilipMondello]

@@RetroCarsForever True that, but if you have time for deep dives, it's a pretty good formula. Either way, nice piece.

[@SaleProofCarReviews]

Now that’s a flattering compliment!

[@GammaRay16]

He's already got DeMuro beat by not being an obnoxious clown.

[@thyubernoob]

@@GammaRay16 My thoughts exactly...

[@larryhankins8960]

i have a 1988 corvette convertible Black iv had it for about 2 years i love it i put a new set of tires and rims my baby killing it ,it gets lots of attention it has 61 thousand miles on it not bad, also had a tune up and two new mufflers she,s in the garage most of the time wanting to come out.🤣

[@Stinger430]

I know I've said it before, but DAMN your car looks friggin AMAZING! It's really a beautiful example. I love a part in the video when the hood is up and you can see how far back the engine is in the bay...almost behind the front axle... I don't have a corvette yet, but I've always planned on replacing the nylon headlight gear to the metal units just as a preventative measure. GM should've used metal from the start. Anyways, enough rambling. Thank you for another thoroughly enjoyable and informative video. Eagerly awaiting the next one. Stay Safe & Stay Warm.

[@RetroCarsForever]

Thank you! Most people don't realize that Corvettes HAVE been mid engined for DECADES, it's a true FRONT mid engined design (for better balance). If you do get a C4 Corvette...Chances are good it WILL have the pop up issue anyways! But thankfully not a hard fix.

[@bassmanbilly1969]

Thank you for such a great video I have just recently purchased a used 1988 Corvette C4 and I will make sure to look out for the things you mentioned in your video God bless have a great day

[@RetroCarsForever]

You’re welcome and congrats!

[@DarrellDavis-r9d]

I used a little black RTV sealant to stop the accumulation of water on the sides of the rear glass hatch!

[@sparnb5602]

2:21 I take my c5 to that canyon in pacoima all the time!

[@RetroCarsForever]

Nice! Love that road, a true tight challenge. Save the Wave if I see ya up there!

[@kelvynwilliams7186]

Yeap,you pretty much got em all,I own 2 c4s,an 84,and a 92,just replaced the optispark,and water pump on my 92,like you said drives like a new c4,love both of them and been through everything you mentioned.

[@RetroCarsForever]

Thanks for the confirmation...Enjoy your Vettes!

[@MrJz97ss]

All those issues are easy fixes indeed. The one other you missed is the oil leak from the back of the intake. At the base of the intake and block.

[@RetroCarsForever]

Yep, another good tip to watch out for.

[@ryantexada9269]

That's a common issue usually when people remove the intake and replace the valley gaskets with those prefit rubber ones. If you put a bead of silicone where the intake meets the block on the front and back then you will usually never have issues. Careful not to put too much though or you can get silicone inside the engine and clog an oil passage

[@yomuno2511]

True. China Wall failure is common on most, if not all SBCs. Replaced the gaskets on my 95 C4 at 62k. Needs replacement again now at 261K. My 86 Quadrajet Z28 replaced at 200k. Much harder job as the metal intake has coolant flowing thru it.

[@derekenlow7607]

If you have battery problems check ALL your connections. I have a fan switch that was installed by a previous owner. A shop must have put the negative wire on the positive terminal of the relay so it worked but was causing a draw on the battery and other issues also. Switched the wire boom door lights on, started right up and the check engine light went off.

[@RetroCarsForever]

Great tip. Especially as many C4s WILL have aftermarket wiring jobs, for alarms or fans or who knows what!

[@derekenlow7607]

I just bought my 1985 c4 3 months ago and yes its going to need a wiring upgrade very soon. Lol theres a sea of electrical tape. Great video thanka for the good info . Another common problem is the electric antenna. Mines currently stuck in the up position had to disconnect the motor till i figure out whats going on.

[@RetroCarsForever]

@@derekenlow7607 I ALMOST included the antenna mast! That seems to be a super common issue too. But I figured that's kinda grouped in with "interior electrics", in that anyone checking out a C4 should make sure that works and assume it doesnt, until they witness it working!

[@richcarrCCC]

@@RetroCarsForever yeah, the all too common "C4 parasitic power drain" problem can also be included in that too I suppose. ;) and of course, the BOSE GOLD gremlins lol

[@nickval5962]

I just knew the Digital dash issue was coming. My uncles 84 has the same issue. I'm surprised the digital dash went before the popup motors.

[@RetroCarsForever]

Yeah, it's a matter of WHEN, not IF, the digital dash is gonna have a problem or two. Im just glad there are some easy aftermarket options to help out with that. Fun fact- 1984 had a one year only gauge design!

[@nickval5962]

@@RetroCarsForever Exactly. I love C4s, Whenever i think of the word "Corvette" its the C4 that stands out to me.

[@ryantexada9269]

@@RetroCarsForever usually the older digital gauges are fine if they're not cracked. Usually the polarizing filter on the gauges just fades from being parked in the sun. If you don't feel like taking the cluster out then you can just put a polarizing film over the faded gauges just to see them if you need to, but once you take one out and put it back in you can have the whole cluster out in 5 minutes and its so simple to disassemble and fix yourself if you have the time.

[@nateminalga1003]

Your videos are great I'm 17 and just got a 1990 c4 corvette

[@RetroCarsForever]

Thanks so much, and congrats! First car?

[@gjsprophet5422]

Excellent presentation. Well prepared, too the point, and with a good dose of humor. i have a C5 but am also looking for a C4. Thus, these tips are quite appreciated. Subscribed also.

[@RetroCarsForever]

Thanks so much! Glad to help. More coming soon!

[@kurtschewe5044]

I have a c4 with a replaced "crate" motor.a locksmith screwed my ignition up.it is for sale

[@lashlarue2266]

Thank you for the video. One item is the high temps above 220 or 230. My car runs just fine at 210, but in parades or heavy traffic, it runs hot. Thus I usually run with air on so that the primary fan is always on and cooling the engine, thus keeping the engine 190 - 210. I consider this a problem.

[@RetroCarsForever]

Not a problem in that range, that’s how the cars were designed! Check out secret quirk number 2- kzbin.info/www/bejne/fp3TYaqkjb2Sqbc

[@josuecortez2259]

Other things to look out for (mainly with later model C4s 92-96'): 1)Crazing or cracking in removable top glass. 2) Vaccum leaks (theres some older hoses in the engine bay that have been discontinued that go bad and you may have to resort to searching a junkyard, or posting on the corvette forum. 3) fiberglass. Sure no rust but fiberglass can be a real pain to work with and its prone to cracking. 4) paint swirl marks 5) finding correct fitting windshield wipers. Finding wipers that can "slide" under and out is of utmost importance. The corvette forum is a great and I mean GREAT resource. 5) CHEAP interior bits. The plastics used in all 90s cars are think and dont last long. They crack, fade and becomes brittle. 6) Seat covers. Mainly the driver side but seats can develop tears and glazing over time. Reccomend buying some leather slip on covers like ones made by Coverking or Igee. They look really nice, arent to expensive, and add a nice new look. 7) Weatherstrip leaks. When installing new weatherstripping, the area where the window meets the windshield trim can still leak. Theres alot of discussion posts on this and I'm still dealing with this to this day. 8) adding headers, not that its bad but its going to make changing spark plugs/wires as well as working on the sides of the motor an even bigger pain. Any time your in a spot where it took alot of work to get there and you dont think you'll need to change out a part, forget that and change it! You don't want to have to redo work. If you change a optispark, change the water pump and gaskets. Change the seals on the timing cover. Change the crankshaft position sensor.

[@RetroCarsForever]

Great tips! Thanks for writing them all down here.

[@tduncan8118]

i just replaced my weather strips and im having the same problem, and suggestions

[@davenobleswimmer7235]

Nice job on covering the main issues of owning a C4 I have the 40th ZR-1 so the do not believe ompti spark system applies to me. I can't believe that the engineers did not think of putting a hose on the weep hole of the water pump to keep the moisture from destroying the ignition, DAH!!

[@RetroCarsForever]

No kidding, that little weep hole would've helped a lot and cost them soooo little to make! And wow...You own my most coveted Corvette...A DOUBLE special edition! I had to give it a mention in my Special Edition video (here if you havent seen it) kzbin.info/www/bejne/rIjLqIGBarGer8k

[@davenobleswimmer7235]

@@RetroCarsForever Believe it or not I saw that video last week. So I just subscribed. Possibly you will enjoy one of my videos at Dave Noble youtube This one is my ZR1 on the NCM track chasing a C8 kzbin.info/www/bejne/p5a0fJJnZ7Sslbs

[@91_C4_FL]

That’s my faded display at 5:30 lol!

[@RetroCarsForever]

A lot of people have taken interest in the C4 Corvette recently,This video took a VILLAGE of people to make, you included. I really wanted to SHOW all these problems, as there arent any videos out there like this are truly edited with visuals. Thanks for helping out!

[@91_C4_FL]

@@RetroCarsForever Of course! If you ever need pictures or footage of a 91, let me know. I’d be happy to help again.

[@neilbenoit7042]

Ive had a couple c4's.Driving a 93 ruby red 40th anniversary convertible now.Only has 22k for mileage.I have fixed the light problem.Brought the car to the dealership to fix the optic spark problem.I fixed the rubber weather stripping.Your spot on with some of the problems for this car.Still is a great ride on a sunny day!

[@RetroCarsForever]

Nice! Thanks for the kind words. Honestly all of this issues are peanuts when compared to a lot of other top tier sports cars of the era. And not too expensive to fix. Great cars to drive and own!

[@t.s.racing]

I absolutely loved my 87. It had the Z-52 suspension option. A big go-cart on steroids. Yes 27 m.p.g. highway WAS achievable. T.S. RACING

[@RetroCarsForever]

Big go kart...Pretty apt! And love how the tall gearing gets great MPGs (on the highway at least)

[@brycejames2127]

The problem with my C4 was the awful cross fire injection. I replaced it with a much better aftermarket setup and intake as well. Runs much better now ! Aftermarket headers and exhaust helps it breathe better now too ! 👍

[@RetroCarsForever]

You must’ve had a 1984 then!

[@brycejames2127]

@@RetroCarsForever yes I do absolutely 💯, runs much better now with the upgrades ! It will fishtail off the line now! Lol

[@Notastonemason]

Late to the party but where did you buy the aftermarket setup instead of the cross fire and how complex was it to install?

[@Athena007]

7:05 - ...the... ALLSPARK?! Optimus Prime can fix that. 😉

[@RetroCarsForever]

I'm so mad I didn't make this joke!!

[@klwthe3rd]

Love your Oldsmobile jacket! Huge Olds fan here.

[@RetroCarsForever]

Sharp eye! I used to own an Oldsmobile, and kept the jacket.

[@WarriorsPhoto]

Great cars. The C4 was such an exotic in the 80's. Now they are forgotten and thankfully so. I'd buy one ☝️. Especially a 96 or ZR1 model. (:

[@RetroCarsForever]

They’re starting to be remembered for the cool cars they were!

[@WarriorsPhoto]

@@RetroCarsForever As with anything. Give it time.

[@Highlander8282]

Another great video! The owner's manual details regular weatherstrip maintenance and notes which product to use. I'm sure most people had no idea. I'm on my second C4 and I only just noticed recently when I was looking through it. I wonder how long it would last if it had been maintained properly. I read somewhere that the early OptiSpark vent hole was changed by the production team without talking to the engineering team about it, even though the engineering team was very particular about it. In doing so, they unfortunately botched it. I learned that the 94-96 have a different drive pin (?) than the 92-93, so they're not interchangeable. One is female and one is male. I actually assumed the steering wheel movement is a clever shock absorbing feature. 🙂 It's the same in both C4s I've had (90 and 92).

[@RetroCarsForever]

Thanks! Never noticed that in the owner's manual, just seems like a good thing to do. I've also heard that the Opti fail is due to one team not talking to the other, but couldn't find a verifiable source (otherwise would've mentioned that in the video). Seems strange that they updated the Opti and didnt fix it, if that really was the case. In general its impressive how many little fixes the Corvette team made on the C4 every year. Steering wheel movement is def NOT supposed to be there tho!

[@exoticsnyc6990]

Building my 93 6-speed to Pro Touring specs. Spot on with the issues. One more thing is that improper service intervals of the ZF trans will result in reverse loss..specially on the earlier ones with the 610 reverse gear. Not using the proper viscosity fluid will make fail quicker. Im C4-Bandit on Corvette Forums and RoadStr app. I drive those roads in the video often. Always up GMR, ACH or one of the Malibu canyons.

[@RetroCarsForever]

Thanks! Great roads in that area. Good tip about the fluid, too.

[@DavidReyes-vr3sg]

Awesome. I am looking into buying a C4 this weekend and this video has ben helpful on things i need to inspect before buy. Thank you

[@RetroCarsForever]

Glad to help, good luck!

[@hullinger]

Another fantastic video and so well done too. Dude, on some of those close-up shots I was wide-eyed on just how fantastically stunning your car is! Wow! Great job pulling together a sort of 'buyers-guide' to C4's!

[@RetroCarsForever]

Thanks man! Appreciate it.

[@topJimmyP1984]

Nice video. The Bose stereo and powered speakers. I also have had the headlight issue.

[@jsprz5928]

The door panels loose and breaking separating from door problem too. Great video keep them coming

[@RetroCarsForever]

Hadnt heard too much about that one...You mean the door INTERIOR trim? Thanks!

[@jsprz5928]

@@RetroCarsForever the whole panel gets separated from door because the ribs that hug the door break on the inside because its poorly made plastic

[@ncrawford1488]

I've had several hood latches break- even my 1991 Calloway Speedster (1 of 12 made from 1988-1992) had the handle break! It had been riveted at some point, and was more work to repair than I expected!!! 1991 ZR1 feels like it won't last too much longer... Fantastic video, BTW.

[@RetroCarsForever]

Thank you. And you've had the cream of the crop when it comes to C4s, wow!

[@franciscelona826]

I have a 91 white coupe with 128k that I've owned for 16 years since 42k. I use it as a daily driver and it's been super reliable after Vats bypassed years ago. All items you stated I've done....headlight rebuilds.... door panel rattles....dash cluster dimming....antenna not going down completely etc. Luckily I don't have optispark (L98) but I have replaced waterpump and passenger window motor. On my third set of tires.....car handles fantastic better than my C6. Also own an 06 XLR built on C6 frame. It is my most fun "Vette" to drive.

[@beegee4401]

94 C4------UGGG---the cost of a door panel for some of these models, and/or trying to find a decent one. Great video and a lot of information in the comments section as well.

[@RetroCarsForever]

Thank you! I've thankfully never had to replace a door panel, I'm sure most of them have seen some serious wear and tear and finding a nice one WOULD be a pain.

[@ssgtkellogg79]

I have a 1991 corvette. Love it, going to upgrade some parts in the spring.

[@RetroCarsForever]

Cool, have fun!

[@michaelwarner2434]

First I'd like to compliment you on the fact that you read and reply to comments. I've never seen a KZbinr do that. I've never been a fan of Corvettes but recently I have an uncontrollable urge to get me a C4. I'll only consider a 96 LT4 with under 50k miles. The only Vettes that I like the looks of are C4's and Ç7's. I'm amazed how many Ç4's are out there with super low miles although I know that isn't always a positive. Seems like the people on the forums sell for fair prices whereas some dealers think one with 20k miles are worth mid $30's.

[@RetroCarsForever]

Thanks for the compliment! Yes I like to reply to as many comments as I can. I had the same goal looking for my own low mileage 96 LT4, hard to find and it took patience and I flew to go buy it and drive it home. But I don’t regret it! And yeah some dealers love to charge wayyy over what these cars are worth. But that’s why I make pricing guides to help people get a better idea. Best of luck!

[@jimstephens9491]

The water pump on my 1994 (80,000 miles) failed and with it the optispark. I replaced both. I also had an exhaust valve spring break. I replaced all the springs, both sides, since the covers were off. I am now looking for targa top weather seals for the entire surround--front sides and back. I can only find the back and side strips without buying the entire set for about $600. The deck and door strips are good, but not the targa top. I had a tire fail after 18 years. I didn't think about the wear due to time and weather. Replace all 4 at Discount Auto for less than $600 with good tires. Thanks for the advice on the C4.

[@Arkablat]

I don't own a Corvette and don't plan on getting one, even though I've always thought about getting one. Still, I want to watch all your videos on Corvettes!

[@RetroCarsForever]

Thanks, quite a compliment! (I've got quite a few)

[@automotiveaffairsshorts]

Came through the C4 fan group on Facebook... this video is really well done 👏

[@RetroCarsForever]

Thank you! Hope you consider subscribing if you haven’t already, more on the way.

[@automotiveaffairsshorts]

@@RetroCarsForever just subscribed... keep up the good work!

[@adambaker2239]

I just bought a 1988 C4 Corvette and I love it so far. I'm really happy you covered the digital dash fading cause that happened with the one I bought but it was the only issue with it that I've found so far

[@RetroCarsForever]

Congrats! Easy fix thankfully.

[@adambaker2239]

@@RetroCarsForever Yes! Very thankful

[@skyking1328]

My high mileage C4 had EVERY ISSUE you pointed out except headlight motors. Additional issues were plastic radiator leak at 140K, intake manifold oil leak off rear of motor, water pump, automatic transmission rebuild, turn signal wonder bar replacement, IAC, constant stone chips on rocker panels and seats were bad condition. My C4 is in nice shape now but it has been a money pit to refurbish. As usual with restoration, have more money in it than its worth.

[@pstreetgarage7304]

Great vid. I have owned my 1990 for 13 yrs now. I agree with all the common issues. I don't have opti spark, thank god

[@RetroCarsForever]

Thank you! Do you have a 1990 L98 or a 1990 ZR-1?

[@jeffu8494]

Just looked at a 92 after watching you video and yup the seat needs an new motor and the guy is getting the instrument cluster fixed. Thanks for the tips

[@RetroCarsForever]

You’re very welcome, happy to help!

[@jpboymoore]

About to buy a 1990, now I’m glad I have a list of questions to ask the dealership

[@RetroCarsForever]

Glad to help, best of luck! FYI a 1990 won’t have an Optispark to worry about (that came a few years later) Also check out this video, and check for the steering column issue- kzbin.info/www/bejne/onLEomWdgNmeprc

[@shaneb2729]

I bought my first ever Corvette back in 15. I was so excited. 93 anniversary ruby red. First yr pretty much trouble free. In summer of 17 i ended up doing a full tuneup, new wires, plugs and opti spark. Ran like a dream. Then summer of 18 I thought I was having misfire issues. Turned out I needed two fuel injectors replaced. Car only has 42000 miles but it sat for a good two or three yrs. I got her back and running as good as new. Thanks for the video.

[@RetroCarsForever]

Not too shabby for an older car that sat awhile. Stay tuned, as im making a video covering all the c4 special editions (including the 40th of course)

[@Steve-xf4uv]

Got a 1990 C4 and love it. I'm not a do-it-yourself mechanic guy so I will be dealing with a garage to fix my car when necessary. It is a 54000 mile original ; I have all the records and Carfax. But now I'm worried that these things you mentioned will happen to my car no matter. What to do !

[@RetroCarsForever]

Just enjoy the car, and make sure you have money saved up in case anything does go wrong. The good news is you've hedged your bets and gotten what sounds like a good example, with records and a Carfax. And you wont have to worry about the Optispark as your car doesnt have one! Enjoy the ride. These are pretty reliable cars for 1990's.

[@kelvinbrooks9588]

Wow! The big media companies could NOT do a better job!! Nice!!

[@RetroCarsForever]

Thank ya!

[@tshafa9468]

Had an 84 that was pristine in appearance. I replaced many items just becausr of age, or while replacing the water pump, I replaced the radiator, fan, and temp sensor to turn the fan on at 185 degrees resulting in a very cool running motor. All the U Joints and CV joints, disconnected the stupid alarm system, all the rubber, including tires, and a new top. Much much more even push rods and rockers for a tad more lift. The injectors was an easy swap. In ran like a beast, and the 84 suspension was rock solid, it handled outrageously well.

[@RetroCarsForever]

Nice! Sounds like a very loved first year C4.

[@herbnalis3723]

I read somewhere about the OPTISPARK prevention to diy fit vent tubes so clean air from the air cleaner is drawn through the OPTISPARK to prevent moisture build up. 1 vent to air cleaner & 1 vent to vacuum source.

[@RetroCarsForever]

Interesting, haven’t heard of that mod before. I’ve only seen the mod where a “drip tube” is added to the water pump to keep it from leaking on the Opti.

[@WuttLives]

I've owned a 1991 ZR-1 for almost 2 years now. It had approx. 35k miles on it when I bought it. It appears to have been well maintained and kept in a climate control garage. I have personally put about 6,000 miles on the car since I've owned it. I mainly drive it easy but have driven it very hard a few times trying to keep up with the other Vettes in my Corvette club. All that being said, the only thing I've had to do was replace the brake light switch and battery. I did swap the A/C system over to the new refrigerant but that was optional. All in all it has been very reliable and the most fun car I've ever owned and I have owned some other hot rods in my days. I love the C4's and wouldn't trade mine in for anything else except maybe C7 ZR-1.

[@RetroCarsForever]

Great to hear! Would love a ZR1 someday.

[@anthonymarkiewicz8653]

Thanks for the Vid. Another area is the door window seals. If you get dirt in them, they will start to scratch the window. Also when they degrade, the window will start to rattle, especially when closing the door.👍👍

[@RetroCarsForever]

Great tip!

[@efrainberrios8494]

I have a 1984…and love it that car!!!…I enjoy your videos too!!

[@RetroCarsForever]

Awesome, thanks for watching!

[@FortunX01]

Thanks for this... I've been trying to find a 1995 one in teal for the longest... definitely going to buy one now!

[@RetroCarsForever]

Man I love the teal color, my favorite, just couldn’t find the right one for me. Best of luck!

[@terrymangrum6142]

Ive got one for sale. 51000 orig miles

[@dominicdoyle2895]

awesome video. Thank you sir. I'm more inclined/less afraid to buy one now

[@RetroCarsForever]

@@dominicdoyle2895 thanks, and no problem! Best of luck with your search. I have several other good C4 resource videos on my channel if you’re curious to know more.

[@malcolmnovar4587]

We have a 1985 C4 which has most of your items replaced..The Bose radio crapped out out on us. Replacing the radio and speakers was a PITA. Trying to get the transformers out if the little plastic wells was a real problems. The SONY radio performs quite well. .finally..

[@tonyg5012]

When I bought my 89 vette ( 2 years ago with 14,000 miles on it ) the headlights wouldn't flip up ( as your video showed ) ...With a little help from my neighbor we got it apart ( I'm a retired mailman , but pretty good with my hands ) We found out it was the PLASTIC BUSHINGS that were completely disintegrated ... bought new plastic gears which came with the bushings and grease ..... Within 2 nights I had the motors back together and back in the car ....

[@TofersCarTales]

Another awesome video, I really love the interiors on this gen!

[@RetroCarsForever]

Thanks...Me too, obviously!

[@johnshields6852]

I do my own mechanical work, this is well done, clear explanations for problems that will arise, what a poor design to put that under the water pump.

[@richcarrCCC]

and once again, Bradman puts up an excellent YTvid, well done... and THANKS!

[@RetroCarsForever]

Thanks man! Curious if you've had any of these issues covered here with your C4.

[@richcarrCCC]

​@@RetroCarsForever sorry, missed your comment! (I could swear I replied, maybe I hit the wrong button or didn't make sure it posted?) Yes, but all but the headlights were disclosed/existed (somewhat) at time of purchase: 1. Weather Stripping - was just rear hatch area but within 6 months the driver door window/targa seal has a tiny "one drop per couple of minutes at higher speeds. 2. Electronics, ironically, your video segment shows you in the sideview mirror, well my passenger side mirror doesn't adjust at all from remote joystick and the driver side only works laterally (not up & down :( ) (Still haven't gotten around to fixing that! lol) 2A. BOSE GOLD typical issues. Bought a new head unit and speaks along with all the adapters etc., but have yet to install lol 3. The headlamp gear/pellets started making noise. (Bought new brass ones off ebay-not expensive) RE: Opti: I drove through more than a few rain storms living here in the PNW, and the opti-spark was apparently never affected, in fact, I entered a parking lot (at work) that before I could back up, well, I drove through "Lake Erie", I was worried about water coming in through the doors more than I was worried about the opti -forgotten about the common optispark+water problem. The car has seen plenty of rain and puddles since then without any sign of problems (KNOCK ON WOOD! Thank God! and thank GM for the Vented Opti ;) ) I have replaced the alternator but that only took $150 and maybe 45 mins and that's a problem with all cars. Your video comes in handy (as is so often the case with all your vids) I trust you don't mind my passing it along from time to time.

[@stricklandgarageaviation2864]

I had the opti problem and I fixed it with a new OEM opti. BUT, I did away with the OEM water pump and installed an electric pump which did away with the possible oil leak where the shaft goes through the timing cover and no water pump leaking problem. The only problem you didn't mention was the dual mass flywheel on manual transmissions. They don't make them anymore. So go easy on your clutch usage.

[@RetroCarsForever]

Great tips!

[@freak227z]

Optispark 😑 my 96 Camaro ghosts are here.... Great video! Subscribed for sure

[@lokihallow]

I put the petris enterprises one on years ago. Love it

[@RetroCarsForever]

Great to hear!

[@shaned1926]

another good vid brad. you have good screen personality. my c4 is 1985. so far I have needed to replace weather seals and gauges, but most likely will need to replace most components both in the cabin and under the hood (standard major tune up items and all rubber components, radiator, electrics ect). yes big(ish) job I got my c4 with the interior nearly completely disassembled as one of the previous owners was trying to convert it to right hand drive (he died of cancer before he finished). I'll be doing a lot of mod work to it anyway.

[@RetroCarsForever]

Wow, that's a PROJECT! Gonna be a totally different car by the time you're done with it.

[@forevadiesel]

Great Positive Beneficial Video 🏁

[@RetroCarsForever]

Thank you!

[@marshapaul1112]

I've owned a few Corvette cars over the past 35yrs. 75, 79 (I kept for 14 yrs) 86, 88 & my current 96. I will NOT drive anything else! So yep I'm a Vette lady! My current 96 has very lil problems. I've owned it for just over 7 yrs. Bought it with 57k miles and now only 65,550. Yep weather striping is an issue along with rattles with the targa top. Electric seat issues with the funtioning custom settings. Over all I've only spent about $2,500 since I've owned the car. So other than jerking up with repairs is been a Damn good car? I Love My "Fancy Girl"!!!

[@RetroCarsForever]

That's awesome to hear! And for a vintage sports car, $2500 in repairs over the course of 7 years isn't bad at all.