oostendarp

Ok.. since I bought my car a year ago (just to drive to work and back roughly 200Km a day) i have had a rich running condition. Fixed and replaced many parts. Recently I took the car to my mechanic who set the idle and fuel mixture correctly so that it is no longer running rich. Since that has happened I now have what I think is three problems:
1) on startup, car immediately dies.. but that is a cold start valve problem and I will bypass that with a switch.
2) if I don't let the car warm up (even on hot days) then when I try to apply any gas, it tries to stall and bucks. Now I have searched the forum and have seen no other posts with the same problem. Could it be that my fuel pump is not sending enough fuel to the system? and it only happens when the engine is cold. After it is warm..no more symptoms at all except...
3) there is a slight burping which happens all the time about every 5 or 6 seconds. I am wondering if #2 and this one are related?
Any help or ideas would be appreciated.

Thanks,
Eva

JAMS6

Not real sure what you mean by burping in #3. #1 and #2 I have experienced before but just lived with it until I got the 20v installed. Mine may not have been as severe as yours. I would start the car 1st thing in the morning and it would immediately die (sometimes die). It would be a little fussy until it warmed up and then would be fine. I would guess the cold start valve is not kicking on and I would suggest fixing the problem instead of bypassing. There are enough parts circulating around for these vehicles that you can find what you need. No point in having a rigged up car, you know? Good luck!

oostendarp

Thanks! I definitely know that my cold start valve is not working.. I tested it with the multimeter, so I will work on fixing that problem. Do you think that my second problem is caused by the cold start valve not working? It has only done this since the CO was adjusted. Could it be that it needs more fuel?
When I said it was burping, I mean that about every 5 or 6 seconds it is like there is no fuel and it is missing a beat. Could it too be that it needs more fuel or that the fuel pump does not have enough pressure, which would seem strange to me. Any help would be great.

4kq4snow

There's a fuel pressure regulator that adjusts the fuel pressure based on the engine temperature. When the engine is cold, it adjusts fuel pressure to deliver a richer mixture ; when the engine warms up the FPR adjusts the pressure a bit leaner. You probably need a good mechanic that is familiar with vw/audi (Bosch) fuel injection. Given the right tools and know-how, it's easy to troubleshoot. otherwise you can take a guess and start replacing parts until it works, which gets expensive.

Regards,
Dave G.

OBTW the Cold start valve is on for 1 -2 seconds when you start the car. After that, it's just along for the ride.

oostendarp

Thanks! I will look at it tonight.