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1997 Audi A8 Transmission issues

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1997 Audi A8 Transmission issues

  #1  
Old 04-17-2011, 12:29 PM
1st Gear
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Join Date: Apr 2011
Posts: 4
Default 1997 Audi A8 Transmission issues

Just bought the car from a repo auction so I figured it would have problems. First one was it was overheating. I assumed water pump, thermostat or radiator. When I got it home from being towed I found it to be low on coolant. I filled it up and the car never overheated. Now I am no dummy and figure I either have a slow leak or something so I know I didnt just fix it. But wierd.

Next is the tranny. After I got the temp to maintain I took it for a spin around the neighborhood. Was fine. Until it got warmed up lets say 20 min or so. Then from a dead stop I would have to rev it up in rpm to even get it to move. I figure it is starting in 4th instead of 2nd. I even tried to shift from 2nd and got the same results. Is is my filter or low on tranny fluid? Does my coolant have anything to do with it?
 
  #2  
Old 04-17-2011, 03:56 PM
2nd Gear
Join Date: Jun 2010
Posts: 624
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First the trans sounds like it was in limp mode...one high forward gear to get you home and reverse...plus all gears lit up at once on display. Sometimes, shutting the engine off and restart will put it back in normal mode temporarily...but something is wrong. A lot of issues can cause limp mode, mostly directly with trans or trans control module. TCM is under the hood (pass side on US models) in the fresh air plenum, under the same cover as the ECM...sometimes moisture can get in there, if rain drain has been badly clogged...if wet in there dry it out and check for clean connections on wiring harness.
Om trans low atf or badly clogged filter could cause problems too:

http://www.audipages.com/Tech_Articl...eshooting.html

If the car is high mileage, 120K or over, unfortunately these trans are prone to several issues that can cause trans failure...the limp mode will kick in when it senses any of many types of failures...you'll have to get lucky for it to be a problem outside the trans...sorry.

GET CODES READ as soon as possible...will help pinpoint the source.

Coolant level should not have effected the trans...separate problem likely. Need to find the source of the leak...they don't get low on their own unless they boil over due to overheating which would be the thermostat. If it no longer overheats at all (dead steady needle on the first big mark once warmed up), you have a leak. Common leak problem if you're unlucky (and no fun to fix....$$$ if done at dealer...cheap if done by you) is the oil cooler's coolant supply pipe (plastic, which decomposes over time, serious engineering mistake):

http://www.audipages.com/Tech_Articl...reinstall.html

If this was the case, you'd find a slow leak at front right behind alternator.

P.S. If you did not refill the coolant with EXACTLY the right stuff (pink or purple "G-12"), you're gonna have a whole new set of problems...if G-12 is mixed with ANY other coolant, it will form a clogging brown sludge...entire coolant system will need to be flushed (preferably chemical) and refilled with G-12 ONLY...no matter what ANYONE tells you.
 

Last edited by silverd2; 04-17-2011 at 04:00 PM.
  #3  
Old 04-17-2011, 07:35 PM
1st Gear
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Join Date: Apr 2011
Posts: 4
Default tranny

You are the man. Everything you said was what happened. I own a BMW 325is and it has the same kinda of thing when the tranny has issues. Whats wierd is we had a hard rain where I live and when I went to get the car the back floor and both front floors where soaked. I at first thought sun roof, but I have heard drain lines in engine area. In actuality when I drove it off the lot I heard a slushing sound from middle console area. Which leads me to your point about moisture in that TCM. Because when I drove it before I bought it I drove it around and tranny seemed fine. I will look at the TCM being wet.

Also I think you answered my other question on this forum about my stereo. When I push the volume on the steering wheel or push in the middle on the acutally stereo I get nothing. I found the fuses on the passenger side but have no idea which one is for the stereo...any ideas?

And lastly it is leaking right behind the alternator....thank u
 
  #4  
Old 04-17-2011, 08:10 PM
2nd Gear
Join Date: Jun 2010
Posts: 624
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The combination of clogged rain drain in the fresh air plenum under the hood (which alone can get water in the electronics box (ECM & TCM) and clogged interior AC drains can flood the interior and center vent canal...very common for both drains to clog.
If plenum drain fills and seeps into AC air inlet (which it common does), it will usually drain back out through the AC drains if they're clean. AC drains clogged alone will spill into left and right of front carpet when using AC, even if outside rain drain is clear. Before I cleaned my AC drains, I once got a shoe full of cold water when turning a corner on a hot sunny day...that was my cue to clean those drains.

http://www.audipages.com/Tech_Articl...tordrains.html

I believe the fuse for the radio is actually in the extra fuse panel in the trunk, above the battery...should be #7, left-middle on that fuse/relay panel. Radio only turns on and off with volume **** on radio head (push on/off).
 
  #5  
Old 04-19-2011, 05:46 PM
1st Gear
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Join Date: Apr 2011
Posts: 4
Default audi tranny

I cleaned out the two orange rubber elbows in each side of the front area. My next question is where is the ecm/tcm controls that might have moisture in it?
 
  #6  
Old 04-19-2011, 06:27 PM
2nd Gear
Join Date: Jun 2010
Posts: 624
Default

Originally Posted by wolfbone71 View Post
I cleaned out the two orange rubber elbows in each side of the front area. My next question is where is the ecm/tcm controls that might have moisture in it?
Under the hood, under plastic cover:

TCM.jpg?t=1303251977
 
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