TCU replacement
04-11-2017, 08:04 AM
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2000 Mercedes Benz E320 4Matic (W210)
TCU replacement
Hello forum,
First of all hello I'm a relatively new user here at MBWorld.
I have a 2000 Mercedes E320 4Matic (W210) M112.941 Engine (3.2L) with 145K miles. Just changed oil at Mavis, Greasemonkey checked my ATF level (have no dipstick) around 3-4 months ago and told me that there was a really negligible drop leak and used about half quart of synthetic dex3/mercon at no charge, just got 3 coils replaced (with their sparkplugs) in my family's mechanic.
The Story:
The commute to school takes roughly 20-30 minutes of light highway driving. At a red light turning into green nearly 5 minutes away from campus the car shuddered rather violently on accelerating and it doesn't accelerate past 15 mph. The engine meter indicates that I'm revving the car however for some reason it's as if its not catching the drivetrain and its revving almost freely. The car on pulling over doesn't accelerate at all now as if its in neutral and even if I switch to reverse it still feels like the car is in neutral.
After lecture, which took an hour and a half, the engine seemed to be cooled down since I was able to reverse and drive for about a few minutes before the engine got into warmer temperatures and the drivetrain stopped working again. I've called AAA and had it taken back to my mechanic and they are waiting on my word if I want to rebuild transmission or scrap the car.
The Diagnosis:
After spending about two weeks researching my dilemma it seems I have found a probable cause. What I suspect is that the TCU has been contaminated by ATF fluid due to a leaky plug adapter that has a design flaw.
Or I might just need a new tranny.
The Options:
I work at a parts store and I was thinking what I could do is buy a new TCU + transmission gaskets/grommets + filter + plug adapter. Bring those to this mechanic that knows how to fix mercedes trannys. Any ideas forum? Thank you for reading.
First of all hello I'm a relatively new user here at MBWorld.
I have a 2000 Mercedes E320 4Matic (W210) M112.941 Engine (3.2L) with 145K miles. Just changed oil at Mavis, Greasemonkey checked my ATF level (have no dipstick) around 3-4 months ago and told me that there was a really negligible drop leak and used about half quart of synthetic dex3/mercon at no charge, just got 3 coils replaced (with their sparkplugs) in my family's mechanic.
The Story:
The commute to school takes roughly 20-30 minutes of light highway driving. At a red light turning into green nearly 5 minutes away from campus the car shuddered rather violently on accelerating and it doesn't accelerate past 15 mph. The engine meter indicates that I'm revving the car however for some reason it's as if its not catching the drivetrain and its revving almost freely. The car on pulling over doesn't accelerate at all now as if its in neutral and even if I switch to reverse it still feels like the car is in neutral.
After lecture, which took an hour and a half, the engine seemed to be cooled down since I was able to reverse and drive for about a few minutes before the engine got into warmer temperatures and the drivetrain stopped working again. I've called AAA and had it taken back to my mechanic and they are waiting on my word if I want to rebuild transmission or scrap the car.
The Diagnosis:
After spending about two weeks researching my dilemma it seems I have found a probable cause. What I suspect is that the TCU has been contaminated by ATF fluid due to a leaky plug adapter that has a design flaw.
Or I might just need a new tranny.
The Options:
I work at a parts store and I was thinking what I could do is buy a new TCU + transmission gaskets/grommets + filter + plug adapter. Bring those to this mechanic that knows how to fix mercedes trannys. Any ideas forum? Thank you for reading.
04-11-2017, 03:45 PM
#2
Out Of Control!!
Sounds very suspicious to me---you use the word "suspect" that is an expensive word that parts pimps love to hear as it means more unnecessary parts sales to novice weekenders---have you or your grease monkey taken the time to open the module box and pull the TCU-----is it oil filled or bone dry?? Has your CEL come on and have you read the faults? bla bla
04-11-2017, 04:25 PM
#3
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'99 and '05 E55 AMG
Put it on a diagnostic system and you'll narrow down the cause. Be aware a standard OBD2 code reader will not read transmission codes on a W210.
Start here by reading the stickies on "drive train/power train":
http://www.benzworld.org/forums/w210-e-class/
http://www.benzworld.org/forums/w210...sion-plug.html
Note: if you get a "hard" electrical fault, the fault can only be cleared by a diagnostic system. So...you might replace parts but still be stuck in "limp home" mode until you clear the fault. A hydraulic/mechanical fault, on the other hand, can be cleared by turning the key off and then on. Much on the interwebz about this....
Start here by reading the stickies on "drive train/power train":
http://www.benzworld.org/forums/w210-e-class/
http://www.benzworld.org/forums/w210...sion-plug.html
Note: if you get a "hard" electrical fault, the fault can only be cleared by a diagnostic system. So...you might replace parts but still be stuck in "limp home" mode until you clear the fault. A hydraulic/mechanical fault, on the other hand, can be cleared by turning the key off and then on. Much on the interwebz about this....
Last edited by bbirdwell; 04-11-2017 at 04:34 PM.
04-11-2017, 05:07 PM
#4
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I don't have the time to check/follow posted links - the good news is 95% of the time faults/issues caused by adapter-plug/TCU contamination can be solved - very affordably:
1. Replace NAG tranny adapter plug genuine MB/MOPAR part only - and NOT no-name/quasi-name part. Amazon as one source $15
2. With a $9 can (less your discount_ MAF cleaner pull and flood clean the TCM board - both sides + connector to the board
3. I have personally never replaced a TCM - big coding thing if you do - the TCM is as rugged as a Nato missle guidance system - but open board can get contaminated
4. No need to preemptively replace conductor plate until comm issues are resolved.
1. Replace NAG tranny adapter plug genuine MB/MOPAR part only - and NOT no-name/quasi-name part. Amazon as one source $15
2. With a $9 can (less your discount_ MAF cleaner pull and flood clean the TCM board - both sides + connector to the board
3. I have personally never replaced a TCM - big coding thing if you do - the TCM is as rugged as a Nato missle guidance system - but open board can get contaminated
4. No need to preemptively replace conductor plate until comm issues are resolved.
04-12-2017, 06:02 PM
#5
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1922 Ford Model T / no OBD
Yeah. "Famous" pilot bushing aka plug aka adapter that cost about $10 but doesn't stop mechanics from making it 4-digits job.
Ask me how did I buy SL500 for $1300
Have the bushing replaced with new one and give good bath to the plug.
Than check the coffin with TCU for ATF contamination. If you see oil there, you need to pull the board and give it good bath as well.
Ask me how did I buy SL500 for $1300
Have the bushing replaced with new one and give good bath to the plug.
Than check the coffin with TCU for ATF contamination. If you see oil there, you need to pull the board and give it good bath as well.
04-17-2017, 02:54 PM
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2000 Mercedes Benz E320 4Matic (W210)
Thank you all for the great replies! Since my post I have found a mechanic that isn't too far and he's willing to take a look at the TCU for any signs of contamination at no cost. I would have done it myself but I'm not really sure where to look I'll admit. From there he will tell me if I need to replace it or if its a different issue entirely. More later this week. Thank you!
