Hello everyone, my buddy has a 2002 a6 2.7 , and I'm trying to help him get it running again, but I mostly work on domestics, this is all new to me. What I know is, it's not getting fuel. The fuel pump does NOT prime, and there is no power at the fuel fuse, but there is power to the fuel relay.we tried replacing the relay, and still no luck.there is also no power at the fuel pump connector. We got a new fuel pump, and hooked it up, and still no change. So at this point I figured I'd ask you guys your opinion that way were not just throwing parts at it.if there are ANY suggestions, please feel free to let me know.also if any further info is needed, just ask.its automatic, and has 150000 miles on it. All I know is one day he parked at his house, came back out a few minutes later and it just cranked no start.later that day, he got in it started, put it in the garage and let it run 15 minutes, shut it off, and it hasn't started since. Thanks in advance for all help

 

Shot in the dark here, but the bold part sounds like the symptoms of a bad CTS (coolant temp sensor).

MIL on? Any codes?

 

Yes there is a code, but that's been on forever and it was a p0700 or 703 something like that for the torque converter circuit I believe it said, nothing even noticeable and the light popped on once in a blue moon and went off like next day. I do appreciate the advice, but can I ask why you might think its the cts? (sorry for the noob questions )

 

*update* we did notice it was low in coolant, filled it, and no change still.

 

you're technically getting advice from a noob himself, so beware.. lol.

It's a common problem with no start symptoms on the A6 (from what I've seen on forums anyway). When it malfunctions it gives the ECU a false temp reading and will either dump too much fuel.. or not enough.

Now I'm not sure if it will completely shutdown the fueling system from the relay on back to the pump, but seeing as how you already replaced the relay and pump (new or used?).. It's a shot in the dark, but I don't think it would hurt checking or replacing the sensor.

It's a $12 or $40ish(?) part depending on which sensor you need.


EDIT: Sent you a Private Message

 

We put brand new everything.i work at a part store so I got the pump and relay for 240 bucks, the the coolant temp sensor I just priced for 8 bucks

 

Just a thought... Immobilizer issue?

 

Immobilizer as in a security issue?

 

Yes. If the key immobilizer is not matched with the car, then it turns off the fuel. Once again, just a thought... That issue is more of a dealer question.

 

Does your friend have a spare key? Did you try that one? Also here is a little discussion about the immobilizer set up. You need a Vagcom though...

Immobilizer III Key Matching (Cluster) - Ross-Tech Wiki