Hi,

I was driving this afternoon and my 04 Audi A6 3.0 FWD died and rolled it in to a parking lot and now it doesn't start. The battery was replaced about 8 months ago and my guess it is the crankshaft position sensor. Also, I can see the fuel gauge working & battery showing 12V on the cluster, as I turn the key to ON position. Could it be something else other than the crankshaft position sensor?

Also where is the sensor located in this car?



Thanks in advance.

 

update - after an hour of waiting I tried to start the car and it started but very rough and shuts down after few seconds. Could it be crankshaft position sensor, fuel pump or camshaft sensors....any ideas?

 

Towed the car home and let it sit there for few hours then went back and tried to start it and only cranks and nothing else. It sounds to me like the fuel pump gave up. I scanned it with a OBD 2 device and showed no codes and tested battery and came up good. Is there any way to test the fuel pump or fuel pressure / system?

Any tips or illustrations will be greatly appreciated.

Thanks.

 

It could be the fuel pump. With no codes it is not the crank or cam position sensor, they definitely throw codes. The pump can fail and then start to work again after it cools down. You can pressure test on the fuel rail under the hood. I know that the newer cars will have VAG-COM errors for low fuel pressure, I do not know about your year. These codes probably will not show up on a standard OBD-II scanner.

 

okay, thanks. Where is the fuel line port located on this car? I looked under the hood and see the pressure regulator but could not locate the port to test it.

Also, I checked the fuel pump fuse and it is good and I thought the fuel pump is located under the rear seat (passenger side) but when I removed the seat I couldn't find it. Is it located in the fuel tank on this 04 Audi A6 3.0 FWD? I see couple wires going through the body and under and a black box with wires connected in the middle and that's it.

 

It is in the tank. Some cars have a schrader valve on the fuel rail to measure pressure. Audi does not do that. You need to tap into the fuel line somewhere. Not usually very fun. When I have had to check this I have loosened one of the joints on the rail and watch for gas to come out. No matter how you do it its a messy job.