Crank Position Sensor Replacement - Stalling 3800 3.8 Engine

If you have a vehicle with the GM 3800 Engine which stalls randomly and may not always restart, then you likely have a bad crankshaft position sensor. If your vehicle runs perfectly but the tachometer sometimes registers incorrectly then you should replace this sensor ASAP before it leaves you stranded somewhere.
I cannot guarantee against unauthorized modifications of this information or improper use of this information. I assume no liability for property damage or injury incurred as a result of any of the information contained in this video. Be sure to read and follow all safety instructions for any equipment seen or implied in this video, and use safe practices when working with potentially dangerous equipment. No information contained in this video shall create any express or implied warranty or guarantee. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user.

[@knurlgnar24]

I'm sure few people care, but I found a 1988 Buick Lesabre with 57k miles and completely rust free recently and bought it. Not sure how long I'll keep it but it's nice to have the spirit of my old car back again for the moment!

[@R.J.Crimson99]

That's awesome man!

[@knurlgnar24]

@@R.J.Crimson99 Unsurprisingly it had all of the exact same issues as my 1991. I used the same solutions as I used on my past car and it's now a comfortable and reliable vintage vehicle that I am able to enjoy. Everything works as it should just like it did new 35 years ago. Cars are meant to be driven and I daily it while my newer ones sit in the garage!

[@Nitro10142]

I know you made this comment years ago but i actually used this video for advice on my 1990 lesabre i got with 59k miles! Best part was i paid 500 bucks for it. I cant stress enough how comfortable this damn car is, despite its quirks

[@darianhanson7845]

Even 10 years later your awesome video Is still helping out! Good explanation. Very well done thank you

[@barnycanuck6234]

Very professional video. Parts were well lit up, you didn't stand in front of what you were talking about, the explanation was to the point and there was no annoying music.

[@matthewschug2158]

I have a 92 century with the 3.3 that has been very hard to start for a while now and the other day it died while driving down the road, it had been running for about 20 min before this. After cranking on it a handful of times it started and ran for about 2 min and died again, third time was the charm it wouldn't restart so I checked the fuel pressure and it rang in at a rock solid 45 psi with no bleed off so next I checked the spark plugs for spark and found nothing. Iv'e never worked on one of these little puppies and wanted a little more help than what the Haynes offered, I can't tell you how much I enjoyed your video and thank you for your time and trouble!

[@kenterr6854]

Nice video. When installing CKP on a 1995 Buick LeSabre a few small tips. 1. When putting in the puller bolts, depending if you rented the puller from AutoZone etc. can be a little tricky. The easy way is to press in and clockwise until you find the opening, then press in and do a turn or two counter clockwise. Then resume threading bold in. 2. Make sure the balancer is all the way in. It may have a type of ridge, where you think it is completely on, but has more to go. Verify that the belt lines up with other pullys. 3. Even though the 1995 is a series I 3800, the CKP sensor and bracket are one piece. So no alignment of sensor is needed. Also, no computer relearn procedure is needed.

[@Cavemaaaan]

This video is an excellent tutorial on how to change the early crankshaft position sensor (a.k.a. CKP). These early CKP sensors are HELL because of the adjustable nature of them. Get the CKP in the wrong position and the reluctor rings will destroy the new sensor and damage the harmonic balancer - ask me how I know this - it CAN damage the harmonic balancer! The 1996 and up 3800 Series II CKP sensor is MUCH easier to replace as there is no side-to-side adjustment to clear the reluctor rings of the harmonic balancer. I changed mine earlier this year on my 97 LeSabre after buying the $15 Lisle adapter kit for my existing HB puller kit. Piece of cake. Thanks Knurlgnar, after just destroying a new CKP sensor and the HB on my Mom's '92 3800, I feel confident again now that I know how to SEE the position of the reluctor rings in relation to the CKP sensor gaps. I gave up earlier in disgust not knowing how to do it. Off to Autozone to get a new HB and another CKP sensor.

[@knurlgnar24]

Glad the video helped!

[@jk359ax]

Thanks for such awesome accurate video. We used similar tools as yourself, however our breaker bar broke on 3rd try. No luck initially with impact wrench. We then put a small plumbers torch on the bolt taking care not to heat anything but the bolt for a few minutes, got it hot, put the impact wrench on the bolt and off it came easily. You are right, bloody bolt almost beat us! Anyway, rest of job piece o cake. Thanks again for such detailed info - job well done!

[@knurlgnar24]

Thanks for the support. It is always good to hear that the video helped someone - I hate seeing these cars go to the junkyard when they're still useful vehicles. Your experience sounds like mine the first time I tried to do this! Ended up putting the battery on a boost charger to give it enough juice to knock the bolt loose! I have since acquired better tools that makes it's removal easy, but I was able to get it done with basic stuff the first time. Broke the breaker bar? wow. Congrats on figuring out a way to get it done!

[@july71961]

***** great video i just bougt ac1999 bonnievile

[@knurlgnar24]

I sold the vehicle back in 2016. It ran like a top with 260k miles the day I sold it despite the body rusting away beneath it. None of the vehicles I own today run as smoothly despite having far fewer miles/years. It was time to move on but I still miss it.

[@genecooley5405]

By

[@bgjobass]

Thoroughly enjoyed your how to video, Sir, thanks for posting. I'll be doing this Crank Sensor replacement job on a 94 Ciera 3.1 liter. 109K miles. It's one of the last two sensors to replace ( the other is the 3x crankshaft position sensor that's located on the firewall side of the motor just up from the oil drain plug area a few inches), as I've replaced everything else I could think of that could cause these symptoms and then some. Your clear and concise description of what to do is greatly appreciated! Many thanks!

[@karenyoung-brown7747]

Standing ovation! Very helpful! This got my husband over the hump! Thank you for simply taking the time to help others!

[@s.caldwelli4163]

Hay Sis always networking huh

[@MOLYRICtv]

Yasssdd

[@saeidaghaa848]

Awesome video and great explanation I ever seen on youtube, for car repair! Indeed it has the best camera position all the time. Thank you very much and God be with you bro! :)

[@flysubcompact]

I'm having an intermittent stalling issue with a 2000 Buick Lesabre. Not throwing any codes or check engine light. Going to give this repair a go. Thanks for great lighting, explanation and narration.

[@TheHaggisking]

Did it fix it. I got the same problem with no coded

[@garrybrewster5821]

2001 model GM Holden Commodore VX series 1 Australian. ,I have an engine service light that comes on, OBD2 Scan gave me multi gear box (auto) errors, I believed this to be jerking and vibration at drive off also through gear change, had gear box replaced from a reck, now the service light comes back with crank sensor fault, it's a rear wheel drive car so this job should be a little easier, really thank you for your time to go out and show your work ...cheers P.S. this car has done 300,000kms ..:) 1/4 million miles

[@carlscarborough774]

Diagram for the serpentine belt

[@jaymoge]

Best tutorial on this job I've seen. No BS, great info, well said. Thanks.

[@81mrmusicman]

great tutorial video on how its done, explained very well and look forward to more of your mechanical knowledge in future vids,

[@green2882]

amazing video. I get frustrated working on cars sometimes and I've never tried to record it. I'd break my phone and burn my car down if I tried. Really really good thanks for this!

[@curiosity2314]

Another great video! Only thing to offer would be to add a note in the video to disable the ignition coil if you are going to use the starter to remove the balancer bolt. I've always done that with the belt still connected and holding the engine back with a pry bar through an accessory like the power steering pump. Just a thought.

[@danielduffy4134]

Thank you for the amazing video!!! Man that special tool makes all the difference in the world. I bought one and now can get the job done Johnny on the spot with know double check and no worries. Get one you will not regret it. I tried it your way before this video back in 2017. Again thanks for the video Bravo………

[@dadfirstalways3578]

Not sure if it's in the comments I read a lot of them, anyway on the back of the mount fork on a series 1 there is an align pin hole that goes thru to the plastic housing of the sensor that gets it as close as you really need without the shuffle on and off. Always check it regardless but hopefully that helps someone in need to not be scared. There really isn't a video like this for those but that's the big change for newer models I'm not sure if this one has it. Saved me hours of fiddle. Thanks for the great vid.

[@astonmarjo]

I've watched both of your videos on this issue , I'll try cleaning it first. My sister will be happy if it works. Thanks 👍

[@badge1957]

Cool !!! Thank you......I'll be working on my 92 Pontiac Bonneville tomorrow...........Bobby

[@HOBODC23]

Great video and one of the more comprehensive CPS videos out there. Thanks to your video I was able to save some cash doing it DIY style.

[@calsir]

Thank you very much for posting this video, I was able to fix my 1992 buick regal 3.8 CPS :)

[@aaronkelly4255]

great video from a learning mechanic thats broke-a s s poor and with an old commodore VS...thanks heaps

[@valeriefairley3031]

putting the nut on the outside of the bolt so it doesn't pull through was brilliant.

[@evilcowboy]

This was a complaint before the engine I am replacing the crankshaft on now shit out. The person noticed random incorrect tach readings and started to stall before spinning a bearing. I bought the car with the idea of rebuilding the engine and wondered if components like this were reusable. Since the complaint was similar I will be replacing this part as well. Thanks for the in depth description of this issue. Most of us would have looked towards the top end for a stalling issue first and this saves some time. Although my engine is completely out of the car and apart this bad boy will be replaced just because of that. The cam sensor seems good so I am reusing that one since it's easy to get to as well. 89 Bonnie will ride again when I am done and I only paid 200 for it so I can afford to rebuild the engine yay for me.

[@knurlgnar24]

These engines had some trouble with the magnet falling out of the cam sensor, but like you say you can always replace it later. It will still run (poorly) without a cam sensor.

[@evilcowboy]

***** lol i might replace it now based on what you just said lol. Don't really surprise me the sensor is from 89 lol I may just replace all of them.

[@knurlgnar24]

evilcowboy Fortunately these engines don't have a lot of important sensors. Too bad the crank sensor - the only one necessary to keep the engine running - is one of the trouble sensors... :(

[@evilcowboy]

***** Has anyone ever looked around for an updated version or somehow custom fit a less troublesome one that you know of? Curious if it could be done. I may look into seeing if the series II one will work somehow. Looks like all they really did was widen the teeth of it. It still has the same number of pins and if the colors are the same I think it may work correctly. It's not such a problem in the series II.

[@channell11]

One trick to help with re-alignment is to mark/measure the old sensor before you take it out. The new one should line up the same.

[@azimmey]

The MOST concise complete video with great info. Hands down the winner! Thank you. Subscribed

[@mikejones9668]

Thank you for posting this video. I just finished with my 1996 Camaro. It took me a while to bust the balancer bot on a front mount. I put a breaker bar on it with a pipe on it pushing down. Although it took me a few hours it was well worth it. Thanks again!!

[@mikejones9668]

Mike Jones balancer bolt I meant

[@mikejones9668]

Mike Jones not thinking clearly--put a long pipe on a breaker bar and had neighbor bump the starter to break it

[@patrickphippspa584]

Wow. You're a natural. VERY intelligent young man! Thanks for your efforts and information. Much appreciated!

[@chrismartin8298]

Be sure to route the signal wires carefully. Be sure that the serpinteen belt is not contacting the new wires.

[@lauraroman3633]

Well done, well explained,thanks for taking the time to make the video, big help.

[@jplunkett3647]

Many thanks for sharing Video was most helpful during repair .. Best part was your suggestion to insert power bar and bump the Starter to break loose the Harmonic LARGE center Bolt .... CAUTION : Don't hold the Power bar by hand rather place it against vehicle I temporarily with some Electrical Wire Secured so my Hands are Out of harms way :o)

[@LouielamsonTranNguyen]

I probably need to replace crank position sensor my 1995 Buick Regal. Thanks for sharing the video.

[@knurlgnar24]

Note that your 1995 Regal will have a different style crank position sensor. That one is easier to replace as it doesn't require indexing. Best of luck!

[@zzman5306]

I just used the breaker bar method for removal. Worked great.

[@Querencias7]

G R E A T job. Excellent video with clear step-by-step explanation (mine is a '94 Regal). Kudos K24. Many thanks.

[@bounty125th7]

Great video and commentary my man...short to the point and hopefully this will help me get back on the road...!!!

[@tonywalters9436]

You just saved me from putting my 1989 Buick in the shop.

[@Lesrevesdhiver]

This CPS seems a common problem on GM vehicles. The job looks to be more of a PITA physically than technically. I once had a 99 Buick with the series II. Sometimes after warm-up and when doing a hard acceleration, the engine would stall and shake pretty bad. Never threw a CEL or anything but does that sound like a CPS starting to go bad?

[@migofromthe7]

bro you fix everything wrong with my car keep the fucking work up man!!!!

[@mikejenmoore2714]

This is a great commercial for Harbor Freight Tools ***lol***. Great video!!

[@larrypickens1821]

Excellent communication skills explaining the steps. Video was very helpful, thank you for taking the time to do it.

[@curtcritt2004]

Really enjoyed your vid. My crank pulley I had to rent a different puller set up but I would've been lost wo your vid. I was about to replace the sensor but I'm not able to turn the engine to check if the teeth are in position 360° so I'll putting on the new crank pulley, cleaning the old sensor and hoping for the best!

[@curtcritt2004]

I have an 89 LeSabre

[@scooter12368]

Excellent, excellent, excellent. you articulate so well and logical. sound like an engineer

[@kennikuhlmann-clark9860]

As a note: the 3800 engine on a 1989 Buick Reatta (probably other models and similar years) should NOT require a 'puller' for the harmonic balancer... As soon as the bolt is off, the balancer will just easily slide off... (there are not even any bolt holes to mount the puller -- If it were to be 'stuck-on' for some reason, all bets are off without destroying the balancer).... There is also no 'dust shield' on my Buick -- or is it actually a shield designed to protect sensor and teeth from a break in the drive belt? (This is, in fact, what happened to the crank sensor; the drive belt split and clobbered the sensor, breaking off one of the lobes, and even slightly bending the reluctor teeth)

[@jonsmith2217]

Good video not trying to tell you what to do it's just how I do things. I got a mat at AutoZone by Wells they gave it to me. It troubleshoots for crank position sensor, map sensor and other things on a vehicle. There's probably something like that online though. I remember on the GM cars of that year you can use the little coin or jump the wires over with a paperclip to count the flashes and look it up. But that doesn't always tell you what's wrong. One thing I always use and it keeps the bolts from getting loose and rusted is blue Loctite. I use it on the harmonic balancer Bolt and a lot of bolts because if things back off the bolt that is it can ruin things. And a balancer bolt it could take the threads out and you need a thread repair kit if you can get the threads restarted to take a bolt. If you can get a thread repair kit without breaking the bank. Also with blue Loctite you don't have to go as tight it's sort of like using Super Glue and that blue Loctite sets up like super glue. The blue Loctite can be removed the red Loctite you have to use heat and other methods to get it off.

[@2OO_OK]

Thanks for the great video. Those bolts you bought are grade 8. The rule is to add 2 to the number of lines on the head of the bolt. So a bolt with no lines is a grade 2. A bolt with 3 lines is grade 5. A bolt with 6 lines is grade 8. Did you say the thread was a 1/4-28? Thanks.

[@knurlgnar24]

I don't remember the details on the bolt threads but I do agree that they were grade 8. Thanks for the comment clarifying bolt grade.

[@2OO_OK]

@@knurlgnar24 You are very welcome. You say the size at 4:40 in the video.

[@knurlgnar24]

@@2OO_OK I added clarification on the bolt grade many years ago but youTube has since deleted notations so that info is forever lost. :( Yes, they are grade 8 as you say.

[@VerifyVeracity]

Great video, Thanks, but what was the scare noise @ 20:26 (27 to be more exact) ?

[@mathewbegnoche2095]

awesome video, I have a 2000 buick lesabre that won't start. No rpm on scanner when cranking. Guess I'll be following your instructions to replace my sensor.

[@benstacy6226]

Great video. My car would not start and I found that my coil pack had a crack due to hitting a deer. I was able to start the car with the broken coil pack with a rough idle. (I didn't know the pack was broken at that time) I replaced the coil pack and I still have a very rough idle thou the car starts right up. Replaced all spark plugs and same problem. Car seems to run a lot smoother at about 2000-2500 RPM. I have 210,00 MI. To my knowledge the CPS is original or at lest hasn't been changed in the last 18 years. Also I ran OBD code and came up with 41. Which says: cylinder select error OR cam sensor circuit. Any ideas would be greatly appreciated.

[@jpoil55]

My auto zone kit didn’t work because the bolts were the wrong size? What are the correct bolts to buy for the 98 Buick LeSabre harmonic balancer? I got the big bolt out using the breaker bar and 24mm socket trick with the starter? Again I just need to know the size bolts for the harmonic balancer using a puller?? Appreciate any info

[@jonoh4883]

Thanks for the upload. I'm actually working on the same 90' Olds Royale and the rubber in my damper exploded

[@knurlgnar24]

Yup, they'll do that. Best of luck to you! At least you won't have to mess with the sensor. :)

[@waltermartin4893]

autozone has a kit called a retrofit kit for the 3800 engines to pull the balancer b

[@tomview1]

Here in Australia, where that 3800 engine is used in our base model Commodore, the crank angle sensors are prone to dying in the arse as shown in this video - the culprit is often a leaking water pump - is that a problem for you guys? Note, Commodores are rear wheel drive, north south engine orientation, the whole job can be done on the floor from above.

[@TheMonolake]

9

[@Clouseau17]

clear and concisely explained, very help thanks alot. i'm no mechanic, what should i expect to pay for this job? Thanks again.

[@jdmackable]

Awesome video, very well explained and thorough. Thanks so much for taking the time to post.

[@knurlgnar24]

Thank you so much for the comment!

[@saxbychaplin1112]

i like very much how your hood opens!! is that a trick you did, never seen one open like that!! thank you much!!!

[@jamesdavies7526]

boy! I wish I had seen the vid before I replaced mine. I spent way to much time on this and I have the manufactures shop manual for all the help it wasn't!!

[@thomasd.lefevre2494]

Sir (or other reader): This is a great and helpful video for the pre series II 3800. Thank you! Assuming the crank pulley on a series II (2003 LeSabre) is the same - would I be able to use 1/4" 28 pitch "pulling" bolts that are 3" long or 4" long equally well? My area hardware stores don't offer 3 1/2" hardened bolts - only 3" or 4" lengths. Thanks for your advice!🙂

[@knurlgnar24]

As long as the bolt threads in fully you're good. If they're too long for the puller tool you'll have to use spacers of some sort. I used nuts in this video but washers or ratchet sockets work too. They don't have to be grade 8 but I wouldn't use ungraded bolts as I don't want a cheap bolt snapping off in the balancer resulting in me having to extract it while swearing.

[@thomasd.lefevre2494]

@@knurlgnar24 You are a mensch! Thank you for your quick reply! Best regards (& wish me luck!) 😀

[@knurlgnar24]

@@thomasd.lefevre2494 Just a note (because it's bothering me) SAE grade 2 bolts are unmarked, so unmarked bolts CAN be a graded bolt. But non-graded bolts are unmarked too so for practical reasons I would consider any non OEM sourced unmarked bolt to be ungraded.

[@jesusdanieldiazserna431]

What a good video I have a buick regal 95 with the problem you said I use it for a while and if I turn it off it no longer turns on after an hour and it has no spark tomorrow I will change the crankshaft sensor and let you know if the problem is solved thanks

[@knurlgnar24]

Good chance it will fix your problem based on your symptoms. If the coil pack is bad you should at least get some life even if it doesn't run, but you'll get nothing at all if the crank sensor is bad. Best of luck!

[@tootall5559]

Thank you That seems pretty close to my 3.3, the same steps should work. Now to get a puller.... later

[@gordbaker896]

Very Well presented. No needless babble or music. It would have been nice to know if it started and the Tach was OK with all this.

[@knurlgnar24]

Originally it started with the car randomly dying when hot and only restarting after cooling for a few minutes. This time I saw the tach doing strange things and replaced it before any functional issues happened. Can't say for sure it fixed the problem but the tach was stable after this.

[@gordbaker896]

@@knurlgnar24 Thank You. The vehicle I refer to is a 1994 LeSabre with the 3.8. She drives to a nearby location and it won't start when she returns. Seems like she has to let it cool down before it will start. Usual things have been checked. I was thinking Ignition Switch or bad ground somewhere. Thanks so much. Sounds like you fixed the problem... again!

[@imtheredbaron]

Great video I have a 2001 Park Ave ultra runs good dosnt stall but 70 mph Ican feel it misfiring. Sometimes the tacmeter needle will bounce and then drop to 0. I got the 0300 code (misfire) couple evap codes 440,449 and the 336 code csps and to top off that the 1811 code which is a trans code which means there is a lag in the shifting. Think maybe the sensor could cause these problems? Car ran great till the service engine light came on. But did notice a little lag in the tranny though.

[@KGtherapper]

I have a v6 3800 1992 Buick Regal, is this the same process to change my crankshaft position sensor?

[@rustynuckles3662]

The thread size of the bolts that thread into the balancer are size 7 mm X 1.0 in-case you need to tap them out to be able to get the tiny bolts started! I had to insert the tap and hit it with a hammer on two of the three holes just to be able to get the tap started enough to clean out the threads. the bolts went in like a dream after that.

[@wedgemac]

Thanks for the vid. friend. Last time I removed a harmonic balancer was on a '71 fury with a 360 in 1989. Very helpful! Peace!

[@jamesdavies7526]

I also had to run a 1/4 x28 tap thru the puller holes to clean them out and yeah the bolts I started with were way too short.

[@psheckman]

we have a 1989 bonneville, That run really rough and won't start when warmed up..We have to let it sit for a good hour then it will start and run fine. It runs great on colder day and rough on warmer days, We have no check engine light. Could it be this? Or the control module..

[@rs2143]

This video is close to the 3.3 thanks it will help

[@specialized29er86]

Here's a handy tip, when removing the balancer best to replace the crankshaft front seal to.

[@SenorSpode]

Hey, knurl, thank you! I'm currently preparing to work on a '91 Olds 98 with the 3.8: the induction cover looks slightly different, coils & belt path are identical. Car owner asked me what it could be, described the symptoms: was running fine, pulled away from light and it lost power and ran poorly, he had it towed home. It started fine for me, after warming up it started skipping beats, then would try to cut out when revving off-idle...finally, it just quit. I told owner it could be (a) crank angle sensor, (b) ignition module or (c) coil(s)...or even a combo. Your advice makes a little more sense, especially in light of the fact that I saw oil slowly oozing out of the top of the oil pressure sensor on the other side of the crank. It's quite obvious. Could the oozing oil have any interference factor or does it not factor at all? I'm good at working on cars and I like to learn from others, I'd greatly appreciate your thoughts. Thanks!

[@SenorSpode]

P.S.--I replaced the O2 sensor and did a complete tune-up recently (5 months ago).

[@knurlgnar24]

An oil leak won't affect the crank position sensor. It is a hall effect sensor and is only affected by metallic objects. Sounds to me that more diagnostics is needed on that particular vehicle. A bad crank sensor will cause the engine to run perfectly and then quit dead with no warning whatsoever possibly allowing a restart and possibly not. Any stumbling is another issue. I'm curious myself as to what the problem is and would suspect the same things you are, but can't offer much help. As a 'shade tree mechanic' if it was my personal car I'd make a trip to the junkyard and purchase an ignition module with coils for around $15 and see if that helps since it's so cheap and eliminates two possible problems, but that's just throwing parts at it I suppose.

[@SenorSpode]

***** Thanks, I'll just dig into it. Crank angle sensors seem easy to replace, as I have the correct puller, among other tools. Also involved is the money factor: said sensor is relatively inexpensive, and the owner's car is very nice, he doesn't mind throwing a little money into it. I'd say that even if we had to get new coils and ignition module, it'd be worth it. The crank sensor is the most difficult of them all, and I can get it. Thanks again!

[@paulie375]

I had this issue on a 3.8 like yours. Went through a bunch of different parts trying to figure it out but in the end it turned out to be carbon deposits building up in the intake manifold from the emissions system.

[@VOX_Games]

So I just replaced this part on the same engine in a 94 park ave, and after putting everything back on, and turning it over, the car will crank but not start and the serpentine is coming off of the balancer every time...when you put it back on was there something specific in the way you line it up? The replacement cps on mine is molded so there was no need to align the grooves

[@MegaViper35]

Do you remember what size the 3 bolts were for the balancer puller to fit it?

[@chucktalley963]

if your interested, heres an update..the hard part was easy..the easiest parts were a pain..balancer came off just slid right off and on..lining up the sensor went perfect..the easiest part took like 20 minutes..was like someone super glued the connection..getting it disconnected without breaking it was difficult but done. new belt was a pain cause it had conformed to the shape it was in while it was in its sleeve..but got it on..car cranked and ran smooth as silk..for exactly 23 minutes and and stalled out as if shutting the key off...going to try the ICM..i noticed it was red hot..car has 2 cooling fans on the radiator..a big one on the drivers side and a small one on the passenger side..i have never seen the small one come on..and the large one only comes on when i turn on the ac(which seems to have its own issue)..wouldn't the small fan help keep the ICM cool?..and how do i know which ICM to buy...there seems to be a few options

[@commitmenttoexcellence]

Very good detail I wish we had the same car because you doe really good explaining

[@YungMikeBeezy256]

could you do a crank no start video

[@EvanDrince]

I have a 2002 Buick Regal LS with a 3800 Motor. It start fine when its cold but after driving, its hard to get it started. Any ideas? Do you think its the crank position sensor?

[@knurlgnar24]

It is not likely the CPS. A CPS problem will cause the vehicle to run perfectly without any issues, or stall suddenly completely dead and/ore not fire at all when attempting to start.

[@EvanDrince]

***** thanks, I will let you know.

[@777jonah888]

+Evan Drince sounds like cps issue to me................there is a site- easy diagnostics 3800that will show you how to test it........cheap enough and should be 1 hour labour at shop or free for diy

[@evanwalker5182]

CG hu

[@waltermartin4893]

autozone has a kit called a retrofit kit for the 3800 engines to pull the balancer

[@dabears9029]

Great video!! watched 10 other ones and this is the best by far! Quick question, did your RPM tachometer work again after you replaced the sensor? My symptoms are the exact same as yours, my rpm gauge even stopped working a few months back but my car didn't start dieing till the other week.

[@dabears9029]

My 2005 impala 3.8 died while driving 6 times.. On the 6th time the engine code finally came on saying 0420 which is the cat converter. But wouldn't the crank sensor cause the engine to run inefficient for the Converter code to come on? Keep in mind I have tried almosr everything to fix this problem

[@evanwalker5182]

hi

[@timestandingstill]

Thank you so much for the information. and your time in putting this video together.

[@knurlgnar24]

You're welcome! I'm glad you found it useful.

[@joedorotik9159]

Very good video.... i have 1992 uick Riviera looks like i have to remove some more brackets to get the pully off... but very much looks like it will help me here.... i am 85 and still do much of my own work on this car.. it has 122k so maybe a good time to change timing chain, magnet, and sprockets? thank you kindly, i subscribed Joe

[@knurlgnar24]

I can't imagine being able to do my own work on my car when I'm 85, congrats to you! I'm not terribly familiar with the Riviera series but GM switched to their 3800 Series II for most models starting 1992. That one has a different (and easier) crank position sensor service and I'm unfamiliar if that's even a common problem on those vehicles - I can say I haven't hear of it before. Something to look up to make sure this vie even applies to your car before you start. Wish you well Joe.

[@rustynuckles3662]

Do you remember what size and pitch the bolts that thread into the balancer are?

[@rogerb.4959]

I have this same car- how do you get the plastic connection off the knock sensor? My crank sensor is good but knock sensor bad. Need to replace it but can't get the plastic connection off of it where the wire plugs into

[@freethevibez]

In you description it says "if you have a jumping tachometer" does that include temp gauge and oil gauge or are you talking about the rpm tachometer?

[@tomsteve3804]

should just be the tach. when at a stop the tach will drop,jump around,or car will stall.

[@savagenomad5731]

I have an 1987 Oldsmobile Delta 88 Royale Sedan with this engine, it doesn't need a whole lot to keep it moving as far as I know, but I'd like to do some tune ups on it at some point, seeing it's my daily.

[@arnoldschmidt2753]

I saw that your oil pan was very oilly,was the crankshaft seal leaking ? Did you inspect it ?

[@knurlgnar24]

The seal didn't leak very much, but most everything on that engine leaked a little. It would drip on the ground if I didn't drive it on the highway every week or so to blow the excess off. I wasn't much concerned about seeps.

[@jayferrante1434]

Six marks on the bolt head is grade 8, 3 marks (slashes) on the head of the bolt is grade 5.

[@chucktalley963]

i bought an 89 lesabre 2DOOR with 77,500 orig miles..it sat in storage for 5 years..ive only driven it a grand total of 25 miles and the stalls started happening..it cranks up so-so and idles pretty good..but after 20 minutes or so it stalls..no sputtering or check engine light or warning of any kind..wait 15 minutes and it cranks again only to stall after 3 minutes..i put my actron scanner on it and the ecm is throwing no codes..i saw your video on cleaning the connectors first..which is what im going to do..but if it turns out to be the crank sensor itself..would it be safe to spray some PB blaster on the balancer bolt for a few days first..i have no impact tools..also are you familiar with this J-37089-b sensor aligning tool?

[@knurlgnar24]

PB blaster won't do anything I expect but you're free to try it! Won't hurt. Modern lithium impacts are pretty competent too. If it suddenly dies as if you turned the key off then the CPS is the most likely culprit and given the very inexpensive nature of the repair I'd suggest just replacing it rather than spending too much time digging further. If that isn't it your ignition module can be replaced for pretty cheap. After that things become more difficult and we'd have to start looking at wiring harnesses and computers and the like. Congrats on finding an original 77k mile vehicle! They are difficult to find.

[@knurlgnar24]

You do NOT need the J alignment tool. Forget about that and follow my video. The tool is useless and no competent mechanic uses it. A CPS problem will not throw a code so that makes sense with your problem. You WILL need either a good impact tool to remove the bolt or do the breaker bar trick I mentioned in the video. No way around that. Some people say you can jam something in the flex plate teeth but I wouldn't recommend that method.

[@chucktalley963]

@@knurlgnar24 i notice you said you had replaced the tensioner pulley already..is it possible to replace just the wheel?..and if so how?.. to look at it it appears to be held on to the assembly with just one 18mm bolt...anything i should know..actually theres alot i should know

[@dwightsolis2495]

what's the size of the bolts needed that didn't come with the kit?

[@angiemaher7103]

1/4-28 x 3 1/2" Fine Thread Hex Cap Screw

[@dwightsolis2495]

Thank you,

[@chucktalley963]

it took me awhile but i finally rounded up the parts and tools i need(i live in the boonies)..so i got the car on the stands and took the wheel off..and wouldnt you know..my balancer dont have the 3 slots to use the puller..it is supposedly called a "slip-fit" balancer ... how do i pull this..reinstall it..and if i damage it can i use a balancer like the one you have?

[@knurlgnar24]

I haven't seen one, but have heard that a few early engines came with balancers that aren't friction fit and so should just pull off. If you have one of these you can put a pry bar behind the pulley and give it light pressure, then use a hammer on the crankshaft (probably on the bolt partially threaded in). After a few hits it should come off. That's how it works on other engines anyway like lawnmowers and the like. For re-installation just run the bolt in to pull it on. Make sure the threads are clean and do it by hand and you won't have any galling issues.

[@46singledad46]

any idea of what this job should cost

[@robertcharnock4878]

What is the torque rating on the Impact wrench you used? Or what is the Model number? Thanks in advance.

[@timestandingstill]

What is the thread size on the bolts you used to pull the harmonica balance? The closest size I have found is 1/4 inch unless it is metric size. I am going to get some hardened steel bolts tomorrow. Thanks in advance.

[@knurlgnar24]

1/4'', 28 thread pitch, 3.5'' length

[@timestandingstill]

***** Already put the crank sensor in, Thanks again. You saved me from spending money I didn't have to fix my car. God Bless.

[@stevensapyak7971]

3.8.15. The bolt threads in the harmonic balancer are: M6 X 1.0 X 70,80, or 90mm length, depending on the puller your using. I used Allen headed bolts & grade 8, 1/4" flat washers. Spray a little lube in the threaded holes first to make sure not to strip any threads. Good video!

[@TheNCGMAN]

thanks this is really what I needed to see.....

[@Whit_Siever]

4 years ago our Buick had intermittent misfire/no start; local shop charged FORTUNE to replace crank sensor and ignition module. Flash forward today, exact same issues have returned from the grave. Swapped ICM, didn't fix Doing extensive looky loo, have noticed leaking gaskets top and side, the side of block is completely soaked in oil and fluid. Wondering if oils/fluids dripping downwards are shorting out the crank sensor Could that be feasible?

[@knurlgnar24]

Oil might make the silicone seal swell allowing water intrusion but more likely will just prevent any corrosion because it's covered in oil. I wouldn't worry about the oil leaks unless you don't want stains on your concrete. That said valve cover gaskets are an easy job. Note that a bad crank sensor will NOT cause an intermittent misfire. The car will either run perfectly or randomly shut-off like you turned the key off and may or may not restart. An educated guess is that your issue is elsewhere. The connections between the ICM and the coils are a common cause of misfires on these vehicles but I'm guessing both were replaced as a unit.

[@Jack51971]

Does the tachometer have a fuse on your vehicle? If so where? Thanks! I have a 93 Park Avenue. I was going to do this myself but the car died in traffic and I went to a shop.

[@knurlgnar24]

I don't know the answer to this question.

[@Jack51971]

@@knurlgnar24 I am told there is no fuse. A shop ended up changing the CPS and the HB that fits over the sensor. Car ran fine for 6 miles then the tachometer got goofy and then the car stalled throwing codes 18 and 41 which are both crank and cam related codes. The CPS was changed 6 years ago and the HB in 2017. Car starts and runs until operating temperature and stalls. The tach is totally dead. Stupid shop did not fix it and they said bring it back....so they can charge me more massive bucks. Anyway I think I have a wiring or computer problem?

[@jgibson111]

Excellent demonstration with great camera work and angles. Not sure how completely this applies to my 3800 Series II SC Buick Riviera (other than the second belt for the supercharger) but it gives me a good idea. Plus I can kill two birds with one stone as I need to replace both the harmonic balancer and the CPS. Great vid. Thanks,

[@flnn5450]

hey, I'm thinking of purchasing a 92 Riviera, but I'm reluctant because of the possibility of stalling problems. I know this is an old comment, but have you ever had any stalling problems?

[@jgibson111]

@@flnn5450 Yes I had it shut down at a stop a couple of times. It acted like a dead battery but it wouldn't restart with a jump or recharge. Had it towed because of that. But my Riviera had other problems. I thought/ hoped it needed a harmonic balancer but it was actually a bad crankshaft bearing. It wasn't worth repairing so I ended up junking the car. I wouldn't let that stop me from buying another one though because the 3.8 L engine is an excellent motor. Mine had been replaced with a junkyard motor before I bought it so no idea what condition it was in.

[@justjulian7503]

How do you know the orientation of the harmonic balancer when you are going to re-install it? I took mine off but didn’t align it correctly now my engine’s timing is completely off.

[@knurlgnar24]

It is keyed and shouldn't be possible to re-install incorrectly. If I remember correctly it isn't even a woodruff key style and therefore can't fall out - though I could be mistaken. Are you sure your timing chain didn't jump teeth?

[@edwardaleman123]

If your having problems stalling when hot or rough idle check ignition Module that is one part most people forget to check

[@stewmiller778]

Just had bad CPS on dodge 4.7L. It didn't stall, but bucked and chugged, especially when you pulled out into traffic and really needed it to accelerate. :-o