Hey everyone, yesterday, I was accelerating from a stop light, pretty normally, not flooring it, and the car unexpectedly downshifted and then shifted back into gear making my wife yell at me, but I didn't do it! lol

It did this twice, ao I decided to drive the car again today and see if it was still acting up. Sure enough, its behaving very oddly. When on the highway, if i floor it, it downshifts like normal, then a second later, it will downshift one gear too far and quickly upshift. for example, at around 65-70, it will downshift into 2nd, throwing the rpm's just past redline and then upshift. normally, it would stay in 3rd gear in this situation. Then at like 80, it would downshift normally, a second later drop another gear, then quickly shift back up even though it was not near redline and i was flooring it.

I have a VAGCOM, if you can provide any troubleshooting steps, I'd appreciate it. I know nothing nothing about troubleshooting transmissions.

3 days ago, I resolved a P0491 (Secondary air flow injection, insufficient flow) by replacing a vacuum line behind the passenger side cylinder bank. I then used the VAGCOM to clear the service engine code, and prior to clearing, i did notice that there were no transmission troublecodes. I haven't checked again since having this new problem, but there are no warning/service lights coming on.

 

So i realize this isn't the easiest to understand. Here is a video showing the issue if it helps.

https://www.youtube.com/watch?v=f1NLodNISb4

This does NOT occur in sport mode, so im starting to think its a computer issue. Maybe something went wrong when I last used the VAG COM. Any thoughts?

 

Now this is occurring in sport mode. I also noticed my steering wheel shift buttons are WORKING now, they haven't worked for the past month.

Please, anyone have any diagnostic thoughts? I am afraid this problem is going to cause other problems the longer i let it happen

 

So i caved in and took it to a transmission shop. Apparently some sort of hydraulic valve inside the transmission has a cracked piston, and it is bleeding fluid causing the issue. Will post a more detailed answer for others who might run into this issue when I get a reciept saying what was done.

Cost $1000. Woohoo.

P.S. Anyone wanna buy a car? Has a brand new transmission valve thingy! $5100
Cars for Sale: 2002 Audi A6 4.2 quattro Sedan in East Peoria, IL 61611: Sedan Details - 320951961 - AutoTrader.com