2002A6Avant

Hi, Please help me ID what that is in the filter below.

Background: I just went through a few weeks of freaking out because I had the dreaded P0741 - 17125 codes. Last Sunday I changed the ATF and filter and the torque converter (TC) started working again... for three days. Here's what happened for those interested:

I purchased the vehicle ('02 Audi A6 Avant) in September '12. In October I replaced all the fluids and filters because I did not know the state of any of them.

In early December the CEL came on with codes P0741 - 17125. At some point shortly before that the car went into limp mode. Limp mode came on with starting the car. I drove it for a few minutes because I had no idea what limp mode was. Then I shut off the car, turned the car back on and limp mode has never returned.

However, I feared the worst with the P0741 - 17125 codes. Because some said the codes, and behavior (the TC was actually sticking open sometimes), could be caused by low transmission fluid, I ensured it was filled per the ZF instructions again. It was, so the fluid level was not the problem.

The TC continued to get stuck open so I was resigned to spending the money to replace it. But then I read that gunk can get loosened with new ATF, which may clog the filter. And I started doubting the Redline D4 I put in it (supposed to be compatible and to spec).

Yesterday I changed the ATF and filter again, trying to get as much Redline D4 out as possible. This time I put Ravenol 5/4 HP ATF in. Driving round trip to work and back always produced the P0741 - 17125 since those codes started appearing. This time the codes did not appear and VCDS reported the TC operating as expected.

During the ATF change I inspected the pan, magnets, and filter. The pan and magnets were normal (no metal, no particles of any size, just a very light amount of sludge). However, in the filter there was a 1/4" clear gelatinous blob, around eight or so black particles, and one almost microscopic piece of aluminum. There were actually two blobs. I picked out the smaller one and it disintegrated when I lightly rubbed it between my fingers. What would these things be? Could my entire transmission be gummed up with this stuff?I'm guessing the black particles are clutch material, not necessarily pieces of the TC seals.

Here are pictures of what I'm talking about.



In this picture above you can see the gelatinous blob.



In this picture above you can see the black particles in the upper right area. The other, smaller blob is also there.

Note: the Redline D4 is red colored fluid.

I called Redline and they have no idea what the blob may be or why the TC would work after a fluid change. Can anyone here help me with these two questions?

A. Is the TC bad? If it's bad, why would changing the fluid make it work for three days?
B. Anyone know what that blob may be?

Thanks!

Regards,
Tom

clancy

Not sure what your blob is. If the fluid has been drained before it could be from incompatible fluids mixing. When you change the fluid unless you activate the pump as some on here have explained, you are only draining at most half of the fluid.

I am assuming you are talking about the torque converter lock up mechanism that is bad and not the actual torque converter. Most on here advocate repairing this when the lock up seal goes bad causing the lock up to stop working properly. I am not of this school of thought. My lock up has not worked for 2+ years and 60k miles. I just keep driving. I've also drained/replaced fluid and filter twice in the last 10k miles. Now the lock up works once in a while, mostly when the trans is cold and I am going downhill with no acceleration. It pops out or off as soon as I touch the gas thus confirming to me that the seal just does not hold any pressure. Also it does not engage at all once the trans warms up. Anyway, my point is that the fact that the dreaded P0741 - 17125 codes pop up are not a bother to me. I expect my trans will eventually fail or the torque converter will fail, but I've put 60k on it with this code and my trans continues to work just fine. Sure I get a little poorer gas mileage, averaging 21mpg, but I also live at 8500 feet and expect that alone is cause for this low mpg.

My logic is why spend $3000+/- to fix this in a 10+ year old car that runs great otherwise? It really does not affect driveability. If the entire trans eventually fails I will then decide whether the repair is worth it. In the meantime I can drive a lot of miles at a slightly reduced mpg for the $3000 I have not spent.

2002A6Avant

Clancy, Thanks for the intel about the lock up working when the trans is cold. I'm experiencing the same.

I'm facing the issue of wanting the sell the car in three years. With the codes popping up would it be difficult to sell here in Colorado? I'm in Colorado Springs. If it would be difficult to sell, might as well fix it now and reap the benefits of improved fuel efficiency, right?

clancy

Sure, you will get more for car that has zero issues. But, will you get enough more to pay for the repairs? And that pesky CEL seems to like to come on for so many issues. Each one can cost significant amounts. Say you fix the trans for $3000 +/- now and then another CEL comes on. You will then need to decide whether that one is worth fixing, etc.

I am not advocating driving a car with lots of issues. That would be silly and perhaps dangerous. I was simply saying that the $3000 +/- repair was not economically responsible for me. Not for only 1-2 mpg. I drive my Audis at least 200,000 miles and generally sell for a minimal amount. A small piece of black tape covers the CEL. It is still visible in case it starts flashing (critical) but otherwise no longer so objectionable. To me it is like getting a small scratch or dent or wear mark on the car. Sure, I wish it was not there, but certainly not something I will spend lots to fix. I fix the important things and let the minor ones go. But then I have not gotten a face lift or a tummy tuck either. Age and its effects are inevitable. Find out what works for you.

2002A6Avant

I thought Colorado has an inspection that needs clear OBDII readiness and no CEL to sell the car. I'm in El Paso county.. looks like I need the car to pass a "basic" test. Err.. maybe not? Info on the 'net is confusing.

clancy

Air Care Colorado handles it in the Denver and north front range. They allow the CEL to be on. Further they have roadside testing where they only look at exhaust as you drive by. No physical inspection.

I don't know about CS. Check your local regulations. Also, if you have a VCDS you can reset the light. Might work long enough to pass. An inoperative torque converter lock up is not an emissions issue.

2002A6Avant

Part of the analysis came back from Redline. The clear gel is silicone. Does anyone know if any of the seals in the transmission and/or torque converter are made from silicone? Or know where the silicone could have come from? Would that cause the TC to fail to lock? Note: I did not use any kind of gasket sealer nor was there any evidence that there was gasket sealer or anything like that used in or around the transmission.

meternerd

Not sure about Colo. but here in California, the 0741 code IS a smog problem due to the reduced mileage when the converter lockup fails. No CEL allowed. My mileage went from 21 mpg to 16 instantly, when my TC failed on a cross country trip. Had the tranny rebuilt and car has been fine for years. If the rest of the car is good, it's still much cheaper to fix it than to buy a new car. Just my humble opinion. My 01 is still going strong at 145K miles.

clancy

You have confirmed one more reason why I am happy to be living here.

A6Gary

I seriously doubt that Audi/ZF used any silcone sealant when assembling the tranny because any residue could come loose, and enter the valve body or some other port, block the ATF, and cause a failure.