hey all. We have a 2003 A6 that is giving me a hell of a hard time. I have been reading all over the forums and just whatever I can find to try and fix this car but it is beginning to drive me nuts.

Here is the scoop:

• 2003 Audi A6 quattro 3.0 Auto
• Suddenly refuses to start
• Engine turns over good but does not start
• I can tell that the starter is doing its job and the battery has good voltage (or it did before all of the troubleshooting)
• No trouble codes
• Checked for fuel pump fuse OK
• Checked for fuel pump voltage ~3.0v ( not so good)
• Checked fuse 34? no voltage
• Assumed fuel pump relay was the culprit
• Replace fuel pump relay
• Problem persists
• Next step says crank angle sensor (crankshaft sensor) may be faulty
• Replace crank angle sensor
• Problem persists

I am currently at a loss and don't know what to do next. I hate throwing parts at a car hoping that it will solve the problem. I would really appreciate any help that you could provide.

 

It is most likely fuel pump, read my posts and I have the same problem and ordered a new fuel pump and waiting for it to come in. The 3.50V is fine and check the voltage at pump connection when cranking the engine and it should show 12V. Connect a multimeter at the fuel pump connection and ask someone to crank the engine and the voltage will go up to 12V. Make sure fuse and relay is connected too while checking.

 

Another option to try is to disconnect the fuel line by the fuel filter and see if there is any fuel coming out while cranking the engine. If not, then most likel bad fuel pump. I ordered mine online since it was way cheaper than buying locay and get the whole set that includes the sender unit if the original part in the car is the same style.

 

I got my pump thru "Parts Geek" at about $275.00 OEM VDO unit. Way cheaper than the dealer or other retailers. Had it in 2 days.

 

Thanks. I got the Bosch 69733 from autopartswarehouse.com for $145 and it came in yesterday. The fuel tank was half empty and got the old one out and swapped it with new one. I just used my hands with work gloves to undo the old pump from the tank and it came out easily. The new bosch pump installed easily as well but it was not tight / seated properly like the original audi pump. Also, noticed that the outer casing on the new pump is flimsy and not as strong the old one so I swapped it out with the old pump's outer plastic housing (top & bottom) which secures to the tank area and installed on to the new pump. It did lock in properly and tight to the tank and installed new fuel filter as well and the car is starting fine with no problems.