illphil4

Greeting,

Sorry for the length of this post, I'm trying to be as detailed as possible about what happen as I have to wait a few days before the shop can look at my car. I want to make sure that driving it in the mean time will not further damage it.

I was wondering if I could get some help trying to diagnose and issue i'm having with my A8. I was on vacation for about 10 days and left my car parked (i drive it everyday otherwise about 30-40 miles a day). I came home started it up and noticed that the exhaust smelt funny and that the check engine light was on. I pulled the codes and got misfires on cylinders 1 & 5 (I can post the exact codes once I get home). The misfires were the only codes being pulled. But otherwise the car was driving perfectly as always. In fact I drove it around for the rest of the day and the check engine light went off by itself. The next day before I could take it into the shop I had to leave town again. It has been parked for about the last 6 days. I get in it today to drive it from the airport to my office and I noticed that the car was idling very rough. The whole car seemed to be vibrating as it was idling. However after a few minutes it seemed to stop vibrating and go back to idling smoothly. As I was backing out of the parking space when I shifted the car from reverse into drive the car started to "slip". I say "slip" because i'm not really sure what was happening. When I put it in drive and the tapped the gas the car sort of lunged forward in a jerking motion. I hit the brakes and tried to put it into park and got a very load clunking noise. I turned the engine off started the car back up and was able to shift into drive with out an issue. I drove it around the parking lot of about 5-10 minutes to see if i could get it to do the same thing again. No dice. Figuring it was a freak occurrence I drove to work. I did about 20 miles on the highway with no problems, car driving perfectly. However once I got off of the highway and back into city traffic at the very first stop light I had the same problem again. Instead this time I didn't even shift gears. I was at a red light and once it turned green released the brake and tapped the gas and it started jerking and lunging as it moved forward. I once again hit the break, and tried to put it in park, and once again got the load clunking/metal dropping noise. Once again however once I turned it off and turned it back on the car drop the rest of the way, including thru many stop lights with out a problem.

My initial idea is that there is a problem with the transmission. Does that sound about right? Or could it have something to do with the misfires? Any help/ideas would be greatly helpful.

jfrahm

Hmm, I would suggest you pull and post the codes.

Did the trans go into limp mode? 'PRNDL" all lit up? Has thre been water in the cowl area?

The misfire on 1 & 5 and rough running makes me wonder about the PCV hose between those two clyinders at the front of the motor. You might whip the covers off and take a look at them.

-Joel.