meternerd

2001 A6 2.7T Quattro. For those who have experienced surging with the Tiptronic....I just bought the VCDS and tried the throttle body adaptation, hoping for a fix. No such luck. Still does it, so I took it out on the road while monitoring torque converter slip (Auto Trans, Measuring Block 007) and slip was going from 0 to some percentage and back under light throttle. As soon as the converter locked, it was solid. So...I did a transmission filter and refill a few weeks ago because it was doing it a little before. Old fluid was just a little dirty and almost nothing on the magnets. I used a digital thermometer held under the fluid as it dripped out and put in the filler plug when it was about 90 deg F. Now that I have the VCDS, I'll recheck level the right way by monitoring it. Turns out the 95 to 113 F mentioned in the Bentley's manual works out to 35 to 45 C, so now I see why it was such an unusual temp. Guess I'm blabbering about all of this to say that the VCDS is an amazing tool. Can't believe I went this long without it. Hopefully the level is off. I actually do have a question....if it doesn't fix it, will I cause any damage driving it as is? I can't see spending the big $ for a torque converter job. Lockup still works fine, so I know the clutch is working OK.

georgeb944

Yep, I have owned my VCDS since I purchased by first 2.7TT car, that with a tip, in 2004. I estimate that it has paid for itself 10 times over on my four subsequent 2.7TT cars and others, too. As a matter of fact, I helped a friend diagnose an A8 tiptronic problem this morning.

As for the Torque Converter Lockup situation, when mine began to rear its ugly head with 140K miles, I asked an experienced Audi Tech, and he said, that it would be good to 300K miles. I will never know if he was right, since someone totalled my car at a stop light at 285K. That said, other than the CEL (which I could turn off for the annual state inspection by clearing the TCU codes, but not the ECU codes), the car was totally reliable and still gave 22 mpg in town and 27 mpg on the highway.

Your lockup will eventually not work at all. The problem is caused by fluid leaking past a seal. Seal is $5, installation is $900.

meternerd

I had the failed seal at about 90,000 miles on a cross country trip. Mileage according to the display went from 24 mpg average to 16 immediately. Not sure why so drastic. I lived in California, so a CEL was an automatic fail, and when I cleared it with a cheapie resetter, it would come back on before all of the readiness codes cleared (clearing the light also cleared out all of the readiness codes). Still a fail without all of those. Since the car was still in great shape, I decided to have the converter repaired and the tranny rebuilt. Had some things inside that were broken (according the shop).

They said the converter got the good replacement seals so should last longer than the car. Anyway....that said, it isn't the converter lockup that's the problem. As soon as it locks, the slip goes to zero. Something to do with the converter not transferring torque smoothly on light load. Seems like a low fluid issue where the converter loses pressure. Just a guess. Maybe an internal pump or valve. If I get the fluid level right and it still does it, I guess I'll live with it. I suppose it still could be something else. Still drives fine, just a tiny bit jerky until the converter locks. Thanks for the info.... I can tell the learning curve on the VCDS is gonna be slow, but educational.

meternerd

Well crap! I rechecked the fluid level by starting the car and adding about a quart while it was cold, left the filler plug out, then waited for the VCDS to show 40 deg C and replaced the filler plug. The amount that dripped back out as it warmed up was almost exactly how much I'd added, so the level was right on. Snowing too much to do a test drive, but I think it's not fixed. If not, it is what it is. I'll drive it that way 'till it dies! Not worth another tranny rebuild.

90SQ

Or S6 is fine but my '98 A8 started doing that at around 250k km, never repaired, only oil/filter changes and it's now at 350k km with no bigger issues...will drive it like that till it dies.