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Is my torque converter going?
10-05-2011, 05:48 PM
#11
The transmission on the 4.2 is not serviceable - meaning you don't normally change the fluid. There is no way to find out the level from what I understand, and in order to change the fluid, one has to remove the pan. So I don't know if the previous owner changed it, I didn't.
Don't be so sure. Bad or failing MAF can reek all kinds of havoc long before it sets a CEL.
10-06-2011, 05:24 AM
#12
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What's the diagnosis procedure for a MAF going bad? I'm experiencing something similar.. low rpm, uphill hesitation at ~10% throttle but otherwise normal performance. No codes. Also 2001 4.2L, 95k miles. Trans fluid/filter done at ~70k so I'm hoping its not TC/trans.
Disassemble, clean, reassemble.. & hope that fixes it?
I watched flow in VAGCOM, but I don't know what the correct value/ground truth should be by RPM/throttle position so I can't tell if the MAF is giving the ECU incorrect flow values.
Disassemble, clean, reassemble.. & hope that fixes it?
I watched flow in VAGCOM, but I don't know what the correct value/ground truth should be by RPM/throttle position so I can't tell if the MAF is giving the ECU incorrect flow values.
10-07-2011, 05:36 AM
#13
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Thread Starter
I am getting transmission oil changed on Tuesday, will report the results. Although I'm doubtful it will help, I need to rule this out before spending $$$ on TC or transmission rebuild.
As for why it's not the MAF sensor - there are no codes, and no CEL. The vibration is not always present, but the RPMs spike up and down - without shuddering, just slippage, as if a worn clutch on a manual tranny.
Coupled with occasional hard shift at 2100 RPM...
The dealer was the one who said the transmission is a sealed unit, does not need to be serviced ??? thus my response that it's not serviceable.
As for why it's not the MAF sensor - there are no codes, and no CEL. The vibration is not always present, but the RPMs spike up and down - without shuddering, just slippage, as if a worn clutch on a manual tranny.
Coupled with occasional hard shift at 2100 RPM...
The dealer was the one who said the transmission is a sealed unit, does not need to be serviced ??? thus my response that it's not serviceable.
10-07-2011, 02:54 PM
#14
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I have similar problems in my 2.7T
I bet the fluid change will not fix anything.
I have the same problems and fluid change did not do anything for me.
My research has led me to the issue described here...
https://www.audiworld.com/forums/sho...4&postcount=14
Valve-body and TC need an rebuild.
VAG-COM will show the TC lock on/off repeatedly while driving. My understanding is the Valve-body is sending wrong data to the TC.
I have the same problems and fluid change did not do anything for me.
My research has led me to the issue described here...
https://www.audiworld.com/forums/sho...4&postcount=14
Valve-body and TC need an rebuild.
VAG-COM will show the TC lock on/off repeatedly while driving. My understanding is the Valve-body is sending wrong data to the TC.
10-08-2011, 05:43 PM
#15
AudiWorld Super User
Thread Starter
That is really helpful information. What you describe makes perfect sense as far as my symptoms go.
Is the valvebody part of the transmission? What I mean, do you disassemble the transmission to get to the valvebody?
Although I'd love to spend less than a full tranny rebuild, the costs seem fairly similar: TC + valve body + labor.
Is the valvebody part of the transmission? What I mean, do you disassemble the transmission to get to the valvebody?
Although I'd love to spend less than a full tranny rebuild, the costs seem fairly similar: TC + valve body + labor.
10-08-2011, 05:57 PM
#16
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Thread Starter
If the problem with our cars is the valvebody (my problem does not appear to occur in the 1st gear, but definitely in the 3/4, and slightly 5th), do we even need to touch the TC? Can we just replace the VB, especially since the TC isn't throwing any codes?
10-14-2011, 11:18 AM
#17
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I would look into shops that might know about the issue. It my understanding that it is a gamble to fix the valve body and not the TC, or vice-versa.
The valve body is bolted inside the trans from the bottom and appears to be easily accessible when the pan is off, but without experience I would not touch it. There are tons of little springs,bearings, and wires in the thing that control the shifts. Leave it to the pros when it comes to servicing transmissions.
Check out the full thread...
https://www.audiworld.com/forums/sho....php?t=2811053
and
Possibly look into a local ZF service location.
http://www.audipages.com/Tech_Articl...zfrebuild.html
The valve body is bolted inside the trans from the bottom and appears to be easily accessible when the pan is off, but without experience I would not touch it. There are tons of little springs,bearings, and wires in the thing that control the shifts. Leave it to the pros when it comes to servicing transmissions.
Check out the full thread...
https://www.audiworld.com/forums/sho....php?t=2811053
and
Possibly look into a local ZF service location.
http://www.audipages.com/Tech_Articl...zfrebuild.html
10-14-2011, 01:05 PM
#18
AudiWorld Member
The VB is more expensive than the TC for one. Secondly, you have to pull the transmission for any of this and that labour alone is close to half the cost of a rebuild. EVERY early 4.2L transmission will need a rebuild eventually, might as well do it all once and save the extra labour costs. $0.02.
10-19-2011, 12:57 PM
#19
AudiWorld Super User
Thread Starter
As promised, update to the situation.
My transmission/TC throws NO codes. However, there were several problems:
1. The RPMs felt like "slipping" between 1200 and 1800 RPM when under light acceleration/load. Gives the impression of a worn out clutch.
2. There was vibration around 1600-1800 RPM under light load/acceleration (noticeable uphill) in 3/4/5 gears, mostly in 3rd in the city.
3. The shifts were slightly hard on occasion, or with slight hesitation.
Decided to change the oil as the first step. So, the result is that #1 and #3 are fixed completely. There is no longer "slippage", and the shifts are smooth as butter, precise and quick.
Only drove less than 100 miles, the shop said it may take a couple of hundred for the new fluid to work its way in and lubricate the clutches before all effect will be noticeable.
I also discovered that vibrations (#2 above) are much less pronounced, though I haven't performed the test in a while. Will drive tonight to a certain uphill road and report my findings.
My transmission/TC throws NO codes. However, there were several problems:
1. The RPMs felt like "slipping" between 1200 and 1800 RPM when under light acceleration/load. Gives the impression of a worn out clutch.
2. There was vibration around 1600-1800 RPM under light load/acceleration (noticeable uphill) in 3/4/5 gears, mostly in 3rd in the city.
3. The shifts were slightly hard on occasion, or with slight hesitation.
Decided to change the oil as the first step. So, the result is that #1 and #3 are fixed completely. There is no longer "slippage", and the shifts are smooth as butter, precise and quick.
Only drove less than 100 miles, the shop said it may take a couple of hundred for the new fluid to work its way in and lubricate the clutches before all effect will be noticeable.
I also discovered that vibrations (#2 above) are much less pronounced, though I haven't performed the test in a while. Will drive tonight to a certain uphill road and report my findings.