Audi 100 Transmission won't shift down
 

Hi everyone- I got two problems, one more serious than the other
1) This 1991 Audi 100 is my first Audi & automatic transmission car as of 12/2005. It drives great, but recently I'd be driving and when I come to slow down or stop, it'll gear down to either 1st or 2nd gear (I don't know), but it doesn't seem to wanna shift up. When I stop and let it sit for 10-15 mins, then it'll drive fine for another 2-3 miles then the same thing happens.

2) When I drive and come to slow down, say to turn or a stop sign, sometimes the car turns itself off. I'd put it in Park and start it. I don't know what caused that, but the idle seems OK. There was a vaccum problem when I first got the, I replace a cut hose and the problem was gone. Now this. HELP PLEASE!! Thank you.

RE: Audi 100 Transmission won't shift down
 

Could be tranny problems. Worn clutches, or just crap in the tranny, clogging the filter, which is a metal mesh screen.

When you let it sit for a while, the fluid from the clutches and servo come back through the screen, flush it, runs for a while, clogs again.

Try a tranny fluid change, drop the pan, clean, flush, run for a while, do it again.

Not hard to do. Buncha bolts to pull, like 16, but spin in and out easy. Careful with the gasket, Audi is good for using a rubber gasket that can be used a few times, and fits over a lip on the pan, rather than most US cars that are flat cork, get a new one.

If you have too, too much stuff in there, you might need a tranny re-build, and a converter power flush.

Cheers,

George

RE: Audi 100 Transmission won't shift down
 

I suspect that the problem is more electrical. The 4-sp is electronically controlled so you might be able to pull some codes off of the ECU. If changing the filter doesn't help I would start with a more generic approach and inspect all the connectors going to the transmission. Over the years the rubber seals and boots crack letting water in and corroding the terminals. Next I would inspect the wires to make sure that they have not rubbed through anything or broken off completely.

RE: Audi 100 Transmission won't shift down
 

Thank you guys. This certainly a lot of help. What should I use to flush the tranny once I drop the pan. And can I reuse the filter and what can I use to clean it with? Carb clearners? Thanks a bunch.

RE: Audi 100 Transmission won't shift down
 

You can clean it but I would just replace it, a filter kit has all the necessary gaskets, seals and filter. All for $20 - 35! Before you toss the old filter examine it closely for metal shavings, some are OK but if you see a lot this could mean more serious trouble. As far as flushing, you need a special machine for this and I think it is more of a marketing ploy. The filter change alone will replace about half the ATF. If the transmission is acting up 99.9% of the time a filter and oil change is not going to help, just my experience.

RE: Audi 100 Transmission won't shift down
 

I just checked my Bentley manual and the 097 4-sp automatic has a second external ATF filter located behind the torque converter/bell-housing looks like a regular motor oil filter. This is a dealer only item.

RE: Audi 100 Transmission won't shift down
 

UGH.. I got your reply a bit late. I went ahead and ordered a filter screen and a pan gasket from BMAparts.com. Great website with cheap parts, I highly recommend it. Thanks to you again Offramp.

RE: Audi 100 Transmission won't shift down
 

You should still replace the secondary filter if you have the type 097 4-speed gearbox. I have seen this filter and it is easy to get to but many auto parts stores don't sell it. I believe Audi recommends changing it every 24K but don't quote me on it.

RE: Audi 100 Transmission won't shift down
 

The gearbox I have doesn't have a secondary filter. I even called Audi and they said only an internal filter is on that car model. I'll replace that with the new gasket I got and hope it'll work.
I can't thank you enough for taking the time, Offramp, to look into the Bentley manual and write back. It's people like you that make the world go-round. God bless.