Originally Posted by tnsparky
js2724 Did you ever find any info on your problems? I'm having the same problem check engine light on, abs+epc on, and p501 vehicle speed sensor code. Same car 2003 audi a4 v6 quattro. I have replaced speed sensor inside transmission but speedo work but back out. I remember reading somewhere that all this might be a problem with ECU.
Hi yes I finally fixed the problem. It was the abs module computer that was faulty. Check out these guys module masters (quick google search will pull them up). They offer a mail in service.
I went to so many mechanics without luck. Finally Greg over at germanautorepairs.com was able to diagnose and solve the problem for me. I highly recommend him if you are in long island, ny.
Hope this helps