Reading spark plugs for diagnosis has it's time and place, especially when tuning vehicles, reading a new set of spark plugs gives a lot of information about mixtures and heat range and engine performance. Other faults can be found by reading plugs also such as oil burning, detonation, pre-ignition and also blown head gaskets in some cases. In fact I diagnosed a Ford Kuga with a head gasket issue on No.3 cylinder just a few days ago, reading the plug along with the misfire when cold negated the use of a cylinder leakage test. A cylinder leakage test was used and showed no fault with the offending cylinder, we have to keep in mind that a cylinder leakage tester will only apply shop air pressure (@100psi) to the cylinder whereas a gasoline engine at idle will normally produce upward of 300psi at idle.
@SchrodingersBox4 жыл бұрын
Why would you read spark plugs when tuning an engine as opposed to using equivalence ratio and fuel trim which gives instant data on the stoichiometry? I can’t understand how reading plugs would be an advantage. what am I missing?
@godfreypoon51484 жыл бұрын
@@SchrodingersBox You can read them to see if the spark plug you selected was too long...
@2secondslater4 жыл бұрын
@@SchrodingersBox the method of dyno tuning a custom engine with fuel injection involves setting up a map for a knock sensor, for instance, from scratch. This is done with the aid of a microphone and headset to detect pinging or detonation audibly and then filling in the map for the frequency the pinging or pre ignition occurs at. Pre ignition and pinging will not always be audible and this is where reading plugs comes in. You can determine if pinging or detonation is occuring in individual cylinders by deposits left on the insulator, there are instances where stoichiometry differences occur between individual cylinders due to manifold design, intake air flow reverberation, differences in intake runner lengths, header pipe length and bend differences, hot spots in combustion chambers and on piston crowns, spark plugs heat range too high, even slight manufacturing variations in rod length or piston pin height can contribute to knocking. Stoichiometry isn't going to address knock completely, an engine with perfect stoichiometry can still knock, this is where plug reading is crucial to determine which cylinder and what conditions the knock is occuring. Then we have old school carbureted performance engines ie dirt track, circuit racers and drag cars where fuel/air distribution is nowhere near perfect and one cylinder can run rich whilst one is running lean and so on, a read of the plugs is very important to run a safe engine tune and select the correct heat range plugs as there is a lack of a knock sensor(s) to keep the engine safe by retarding timing or richening up stoichiometry or both. There is a lot of history and documented procedures and case studies for reading plugs, it is a skill that many don't have, and that a lot that do read plugs, do incorrectly.. It is not some black art and does not involve guess work. Even manufacturers read plugs during engine development dyno tuning or in on-road testing phases.
@flightofthefatman4 жыл бұрын
@@2secondslater Man I know nothing. 😔
@SchrodingersBox4 жыл бұрын
how does reading plugs help determine detonation better than a scantool with knock sensor PID or a scope on the knock sensor? Seems to me getting real time live data for instant validation is better than running an engine with detonation long enough to see it on the plugs and not even being able to determine it anyway.
@frugalprepper4 жыл бұрын
I knew that cylinder had a hole in it as soon as a saw the spark plugs. I could have diagnosed the rest with a vacuum gauge. Of course you have to wonder if the engine damage was actually there before you saw it.
@SchrodingersBox4 жыл бұрын
Ha!!! Schrodingers engine damage box!
@billsmith22123 жыл бұрын
Would a basic cranking vacuum test indicate a failure ? It would not reveal where the problem is . But you would know that the engine is not sealing and pulling a specific amount of vacuum on a good crank - with the throttle WIDE OPEN . I think vacuum testing is often overlooked . It is quick and can point you in a direction . I don't have a back pressure guage . But a used the vacuum guage to diagnose a clogged cat 😺 on a friend's Honda Accord through the oxygen sensor hole . If I was Bernie Thompson from ATS , I could have run a volumetric efficiency test through an E Scope . I bet most DIY's don't have one !
@SteveLowe654 жыл бұрын
My thought on the middle cylinder is detonation damage. Overheating engines will knock like a Jehova's witness, piston's new name is Chip!
@reneneron29714 жыл бұрын
Steve Lowe agree. Engine was severely overheated, then started detonating damaging pistons. I suspect the hole in the middle cylinder was caused by a chunk of metal from the top of the cylinder head.
@int531854 жыл бұрын
Good diagnosis! Wouldn't be the first time a 'customer' lied, or at least stretched the truth. Probably was overheating for a while, causing the oil to cook and destroy the timing chain, tensioners and guides. Finally reached a critical phase, warping the cylinder heads and block. With detonation due to high cylinder temperatures causing disintegration of a piston caused by high frequency shock waves that literally hammered out a piece of that middle piston. I had one of these motors with over 200K miles on it and it still ran good. Lack of maintenance spelled disaster for this engine.
@Face2theScr33n4 жыл бұрын
Another inspiring video from a good man. Thanks, Matt!
@kman-mi7su4 жыл бұрын
Thanks for showing the "post mortem" exam! Today was a pretty good day, unless you're the owner of the Mazda. Keep the awesome videos coming. I'm going to buy one of your t-shirts.
@SchrodingersBox4 жыл бұрын
Thank you!!
@50sKid4 жыл бұрын
This guy absolutely roached his engine! Good lord!
@flightofthefatman4 жыл бұрын
Thanks for the follow up video. Parts changers are good for the economy.
@89531474 жыл бұрын
Thanks for the money shot Matt- appreciate the tear down!!
@theautomotivegarage4 жыл бұрын
Another - Great Quality Video Sir, very Informative and Educational. Learning something New everyday. - Every-DAY. .Thank You!!!
@50sKid4 жыл бұрын
Ooo, you're turning bolts! My my, things have changed around here lol. ;-)
@Agent-nw3it4 жыл бұрын
Yo dude! You're alive! I guess you've just finally fixed all the issues on your E46 :)
@prikolasvaikstantis86134 жыл бұрын
@@Agent-nw3it how E46 can be fixed? It's bmw you can't fix bmw and drive it more than 1000 km without new problem..
@Agent-nw3it4 жыл бұрын
@@prikolasvaikstantis8613 I know, I am trying to convince him to start making videos again :)
@Honky_Konky_Phooey4 жыл бұрын
Another quality video, always look forward to seeing the next episode. Keep up the good work fella 👍
@OneLegged-honda-mechanic4 жыл бұрын
Don't you just love seeing engine carnage 👍
@SchrodingersBox4 жыл бұрын
it’s like an autopsy!!
@jrautotech69924 жыл бұрын
Great video I love all your videos thank you for sharing and God bless you.
@RobertCiampa91124 жыл бұрын
GM You keep a well organized shop
@simonilett9984 жыл бұрын
Sweeet....Ummm guess we found the coolant leak🤣 and we may have just seen a cracked intake seat or 2 there too. And maybe that odd looking cylinder was the only survivor👍🇦🇺
@charlesajouri72334 жыл бұрын
And that's why i only buy toyotas and take care of them. Thanks for the videos Matt.
@quintonm86094 жыл бұрын
I think reading spark plugs is for the most part obsolete, although, I do think there is some good science behind it. For instance, if you pull a plug out of a car with a no start and it's melted... Well... That's some good information. Otherwise, you can get all the other information from a scan tool and by using the big pink thing between your ears and behind your eyes. What's that called again?
@worsttintentions4 жыл бұрын
Are you thinking about pulling the pan off? I gotta know where that piston chunk went unless it lean burned a hole in it or sent it through the exhaust. Side note, it may be lodged in the cat.
@SchrodingersBox4 жыл бұрын
Good idea!!! Yeah I think I will do that!
@motordad8754 жыл бұрын
Yes I would love to see that too.
@worsttintentions4 жыл бұрын
@@SchrodingersBox Awesome, looking forward to it if you make a video on this channel.
@godfreypoon51484 жыл бұрын
When I read your last note, I mentally heard the meow of the intro cat.
@georgebonney904 жыл бұрын
Im luvin all this great content, thank u sir
@SchrodingersBox4 жыл бұрын
Thanks George and congratulations again- are you able to access the paid channel now?
@georgebonney904 жыл бұрын
No sir im still unable to access ive tried afew times
@name92874 жыл бұрын
You are my automotive teacher :)
@SchrodingersBox4 жыл бұрын
It is an honor! Thanks for letting me share my experience with you!!
@baddriversofnorthtexas68504 жыл бұрын
I had an 05 mazda6 with the same engine, same mileage, and it had compression issues also. Hopefully the design flaws didnt carry over into the skyactiv engines. Although I hear that gummed up intake valves are popular because of direct injection.
@alanscrivner18814 жыл бұрын
Polymerized oil in #3 is my guess for that nice smooth black finish. It's a nice thing to have on cast iron cookware, but probably not ideal for the inside of a car engine. I wonder how many times he brought the engine up to the oil's smoke point to get that nice of finish?
@TheEclipsegsx984 жыл бұрын
But polymerized oil in #3 would not reflect on the spark plug of that cylinder right 🤔 or rich/lean and timing advance would not reflect on a spark plug either right! Like your comment it shows that's there's some kind of information we can still get of the spark plugs (not for damage in most cases) but still useful info 👍
@alanscrivner18814 жыл бұрын
@@TheEclipsegsx98 I'm not a spark plug whisperer. I'm also illiterate when it comes to reading spark plugs. Sadly, I have to rely on my scan tool for rich/lean conditions or timing issues. Instead of subjective spark plug observations, I'm stuck depending on objective data (at least for cars after '96).
@TheEclipsegsx984 жыл бұрын
No doubt scan tool it my first to go tool but i do believe that spark plugs do have their spot in the process of gathering all the info to see the engine's performance and state. Good input on your comment 👍
@robbedoeslegrand2364 жыл бұрын
I can't believe you totaly missed the fact that there are 2 cylinders missing in this V8 block!
@northpoint10394 жыл бұрын
Couldnt help but notice that the coolant ports on the block looked pretty clogged. Could that have something to do with the overheat?
@SchrodingersBox4 жыл бұрын
Great observation!!! I didn’t notice that!
@danb78564 жыл бұрын
Good video. Be good if they were timestamped for different sections of repair so we can refer back to them
@spelunkerd4 жыл бұрын
Funny, even with the bell clicked I don't get notification. KZbin robots are making executive decisions based on other factors.
@Pablo_Automotive4 жыл бұрын
Well done Matt =)
@parreiraleonardo4 жыл бұрын
Hello from Portugal 👍 the Lauch CRP Touch Pro that you use is really compatible with almost any car? Or it is compatible just with USA cars? I was interested in that tool but I'm worried that it wouldn't be compatible with European and diesel cars that we have a lot in south Europe. Also, I'm only finding on ebay the Touch X129 and the Touch Pro Elite version (about 250-300$)... Not exactly the same as the Touch Pro that you have with that green button and those buttons on the left side...
@SchrodingersBox4 жыл бұрын
It is not only compatible with just about any car but it actully connects better on asian and european cars better than my other scantools.
@parreiraleonardo4 жыл бұрын
@@SchrodingersBox thank you for the answer. By the way, there is any cheaper scantool on the market that is as good as this one? Or 250$ is the cheapest/quality that we can get? The cheapest is the CRP 129X version. Is it as good as the Pro or Pro Elite Version?
@SchrodingersBox4 жыл бұрын
Man, any less than $250 and you are not likely to have the features you need. You can start with a CRP 129 but once you develop skills you will wish you invested more.
@ralphvaccaro26383 жыл бұрын
Good job on the video 😀
@SchrodingersBox3 жыл бұрын
Thanks! 😁
@govhickenlooper4 жыл бұрын
But we love parts changers.
@SchrodingersBox4 жыл бұрын
Hahahaha you kill me dude!! Goddammit WHO IS THIS??
Did this engine warp as a result of interference or was it overheated as well?
@randomugliness12384 жыл бұрын
Although thinking about it more you said that when the car died on the owner they said they saw white smoke. So I'm guessing engine warps due to the internals meeting and then took the head gaskets with it.
@SchrodingersBox4 жыл бұрын
the warp would be from heat for sure. This engine must have got ridiculously hot.
@Face2theScr33n4 жыл бұрын
@@SchrodingersBox Seems to me you must be correct, the side with the horrible warping in this video must have been serious-as-a-heart-attack hot!
@markboheman56914 жыл бұрын
I’d love to hear your current thoughts on the pandemic.
@SchrodingersBox4 жыл бұрын
I believe we are going to see the pandemic miraculously disappear after the election.
@InsideOfMyOwnMind4 жыл бұрын
@@SchrodingersBox You are only one of about 50 people who have said that to me word for word. How sad, after all those who have died that it will come down to children playing on the hill.
@int531854 жыл бұрын
@@SchrodingersBox At least Pelosi's hair looks good!
@flightofthefatman4 жыл бұрын
Have the Democrats so far said anything about Russian interference this election? I'm guessing not but would like to know.
@zeferrum4 жыл бұрын
Schrodingers Box can you expand a bit more ? As a long time viewer from Canada this statement is ambiguous and I would love to hear or read your complete thoughts.
@sethblackmoore30574 жыл бұрын
Would a starter from a American spec v6 work on a Japanese spec 4 cylinder?
@SchrodingersBox4 жыл бұрын
depends on teeth in flywheel and starter design.
@sethblackmoore30574 жыл бұрын
@@SchrodingersBox ohhhh ok thank you for the reply
@edwardthor77634 жыл бұрын
"We've got the worse warp I have ever seen and catastrophic damage to a piston today is a pretty good day." So has the job and society warped him a little?!!😂
@shaunewing89734 жыл бұрын
I’ve rebuilt so many of these heads . There junk
@billyr98404 жыл бұрын
Nice !
@Barnekkid4 жыл бұрын
I'd like to join your community but is there some way I can prepay for the whole year, and more importantly, can I use paypal?
@SchrodingersBox4 жыл бұрын
Sorry but neither option is available at this time. Payment is through Stripe- a secured credit card service commonly used through the industry. It’s very secure.
@ismarmeskovic4 жыл бұрын
i strongly disagree with your statement 2:07 .you can diagnose / read from the spark plugs if you know how mate!
@stupersyn14 жыл бұрын
Maybe after that you can read my tea leaves.
@SchrodingersBox4 жыл бұрын
EXACTLY Eric!! One of the the main variables with reading plugs is the very first thing most people do when their car acts up is change the plugs. They can’t change the fuel trim though!
@ismarmeskovic4 жыл бұрын
@@stupersyn1 will do right after i complete shade tree mechanic course mate 😀
@stupersyn14 жыл бұрын
@@ismarmeskovic 😂
@InsideOfMyOwnMind4 жыл бұрын
"But it never overheated." When you do that engine swap I hope you also go through the cooling system including belts, hoses, check any fans and the radiator. Likely you will find some things like, I dunno, maybe the root cause?
@SchrodingersBox4 жыл бұрын
Absolutely!!!
@crisprtalk69634 жыл бұрын
I read the plugs to tell the future... mine say I am screwed!
@seiyoseki58514 жыл бұрын
Hi Matt, Sensei, I’m from Japan. I have joined you website community recently, I’m wondering if I can call you or something, I’ve got some troubles with my car and there is no trouble codes detected, both LT and ST fuel trims are around -9% at idle, gasoline consumption is like crazy high.
@SchrodingersBox4 жыл бұрын
I would start by checking for a damaged fuel pressure regulator diaphragm
@seiyoseki58514 жыл бұрын
Schrodingers Box thanks a lot for the tip, and I have just noticed when I was driving the car , every time I release the throttle, STFT goes back to 0% and it stays at 0%, then if I hit throttle again, STFT goes positive to 3-6% for 2, maybe 3seconds, then STFT just drop down to negative -15%~ -6%, LTFT just stays around -9%. PS: Super glad to join your community.
@SchrodingersBox4 жыл бұрын
Even more evidence of a fuel pressure regulation issue
@seiyoseki58514 жыл бұрын
Schrodingers Box Thanks so very much, I will replace the regulator and see what happens then. Thanks again, thanks
@SchrodingersBox4 жыл бұрын
I am not saying replace it- I am saying it’s a likely variable.
@ajlal134 жыл бұрын
I've come back after a loooong time as life happed. Are you still providing the paid video training?
@SchrodingersBox4 жыл бұрын
Welcome back!! Yes I am. It is at www.schrodingersboxqm.com.
@m721ac4 жыл бұрын
is his temp gauge working fine?maybe thats why he claims it never overheated.
@m721ac4 жыл бұрын
btw, do you ship your shirts overseas?
@SchrodingersBox4 жыл бұрын
Yes the shirts are from Teespring and they ship overseas.
@jefferyjensen31794 жыл бұрын
Could the missing pieces of the interference be held in front of the cat?..
@SchrodingersBox4 жыл бұрын
Absolutely. They often get pushed out the exhaust valve.
@prikolasvaikstantis86134 жыл бұрын
I would check if injector for cylinder no. 3 isn't leaking...
@SchrodingersBox4 жыл бұрын
Ah good idea. That could explain the discoloration.
@technomage67364 жыл бұрын
With this kind of overheat, I wouldn't be surprised if anything happened
@PhillyDee2154 жыл бұрын
Engine is toast😱
@robertmedina68754 жыл бұрын
Man you got a short one Matt 🤣🤣[ruler] I am laughing with you my friend not at you..joking lol
@mrt53544 жыл бұрын
👍
@dennisgundlach874 жыл бұрын
I see you have a rake in your garage
@SchrodingersBox4 жыл бұрын
Yes it’s my home garage.
@dennisgundlach874 жыл бұрын
@@SchrodingersBox yeah just being funny, really do like your video's, good content and info, keep them coming, you also have a shovel