:andrew

Hello, my car is a 97 Audi A4 Quattro (V6 2.8 12v). My car this past week was taking a long time to start, and now it will not start at all. The engine is turning over but it will only briefly sputter and then cut right back off. Sometimes it will backfire a little. This problem would began when the temperature here dropped into the teens, but now even when it has warmed up, it still won't start. Another thing I noticed is that oil is constantly dripping from behind the oil cooler.

Here is what I have done/know
- the fuel pump is working
- replaced the battery today
- somewhat recently replaced the coolant temp sensor (2 yrs ago)
- no coolant in oil

Thanks in advance for any advice...

:andrew

Disregard the "would" after this problem...

4Driver4

Replace the oil cooler o-ring first. Then replace the coolant temp sensor. 2 years is not "recently".

This is, of course, just a guess. Some codes would certainly be helpful.

:andrew

UPDATE:

The weather here has warmed up and I managed to get the car started. It took a few tries to start it, but once it did it idled like crap for a few minutes (which would intensify if I hit the gas)then would run fine. I drove it around for several miles and the car drove normal. When I start the car right after driving it, it starts up quickly with no problems. However, when the car sits for several hours it becomes difficult to start again.

twentysevenlitres

I had almost the same symptoms on my S8 when I first got it.
I also had pinging from the engine under load.
This indicated fuel starvation, despite the fact the pump was obviously working.

Problems were likely to be:
1. Low fuel pressure. Causes:
- clogged fuel filter
- bad fuel pressure regulator
- clogged lines
- failing pump

2. Bad injectors or injector leak down.

After replacing all the cheap items and performing a flow test, I ended up at the pump.
Although I did replace the pump, I eventually found that I had a partially split high pressure fuel hose on the pump assembly which was pumping half the fuel back into the tank.
So in my case, although the pump was fine, it was also the location of my problem.

:andrew

Thanks for your response. I think I have narrowed the issue down to be fuel related as well. Unfortunately, I am on the road traveling right now and do not have any tools or time to work on it. So I had to take the car to the dealership.

:andrew

Another update:

Well, the car was at the Audi dealership for two weeks and they didn't find anything wrong (I think they were putting it off). I have since got the car back and begun to try and diagnose it myself, and I think I've found the problem. First I found out that I can easily start the car with a can of starting fluid, which led me to believe it's a fuel problem.

Second...Does anyone know if the on board diagnostic code for the engine coolant temperature sensor that you can get to display on the climate control is showing you a digital value of the temperature it is reading?

Here is a link that shows the climate control codes...
https://www.audiworld.com/tech/int5.shtml
It is number 26. If this value is a digital display of the temperature the ECT is reading, then mine is definitely bad because it is stuck on 15 and doesn't change no matter how long I drive the car.

Also, last night I noticed the coolant temperature gauge needle would sometime drop all the way to cold and then move back to the middle periodically. I am pretty sure a bad ECT is why the car won't start once it cools down, but I would like to know what that OBD code value means just to be certain.

4Driver4

Two weeks at the dealer?! Why not drop $20 on the sensor? Just change it. If nothing else, it will eliminate it as a possible cause.

Why so reluctant to change it?

:andrew

I'm not reluctant to change it. I am really just curious about the OBD display. I have already ordered the part. I would have just bought it from the dealer, but I don't feel like giving them any of my money.

A4QuattroV6

I am having the exact same issue. Andrew, when you think it won't start, it will. It just takes 20 + cranks. It doesn't seem to matter how long the engine is cranked each time. It just gets closer to running every time the key goes from off to start . This started when the super cold moved in for me too.

:andrew, does this sound familiar?
http://www.youtube.com/watch?v=d0uXF...ature=youtu.be