2004 A4 Will Not Start

Have a '04 A4 1.8 T that sometimes will not start. Have had it into the dealer 4 times and they couldn't find a problem. The warranty is now expired. Any suggestions?.........Throttle position sensor?..........Oxygen sensor? Fight the dealership? HELP!

I've ran into this problem a couple of times. Where the car battery is still good. It's the knock sensor that should be replaced. I recommend getting the car scanned for the fault first to make sure. Good Luck.

if the mechanics cant find anything wrong with it and you know for a fact theres something wrong, you're going to the wrong place
Spark plugs working?

Got it fixed. The dealer replaced the fuel pump but not the relay. After talking to the G.M. about the ongoing problems, they agreed to take another look. They replaced the fuel pump relay and it's been running great. Thanks for everyone's suggestions.