03 chevrolet malibu won't start every couple of days?

[Joey]

Around a month ago my Malibu would not start. I had to beat run it to the shop, where they replaced the plugs,wires, and fuel filter(which was all stock at around 62980 miles) this seemed to solve the problem until about a week ago when the same problem occurs. We took it back to the shop where they replaced vaccum hoses. This solved the problem for 2 days. When the problem occurs the engine tries to turn over but just won't Catch. If you apply the gas pedal the engine roars to life but once the pedal is released and the rpms drop to 0 the engine dies. For some reason the car usually starts if you keep at it for a couple hours. Another thing that worked was keeping the gas pedal pressed for a while (20-45 seconds), the engine finally kept itself running. I've been told this could be the fuel pump. Another person told me it could be the fuel pump and the throttle position sensor.
the car is now at 63153 miles.
Have not noticed an oil leak. There is a fuel smell when trying to start it. The mechanic said it have something to do with a bad ball in the pump?something to do with the fuel pressure not being great enough

 

[Andrew4632]

I'm asuming this is 3.4L engine? Even if it's not, try cleaning the throttle body (or preferably taking it to a shop to have it cleaned) a good throttle body clean, should be the first step towards finding the problems, before the wires and plugs and everything was changed.

I doubt it would be the fuel pump! You would probably have other driveability problems.
Umm.. I work at a shop (this is probably a long shot) we had a customer with a very intermittent no start (same car, similar symptoms) it was the computer (ECM) we gave it a whack and the car started right up, gave it a hit again and the car would quit..

Check the throttle body first though..

 

[diesel]

It's not your fuel pump unless it sqeaks when it does start. But... Have you checked the battery? It is very likly it could be the battery. They checked about everything at the shop. Does it leak oil when its start and ride it then let it sit? You could have a bad head or something. Check for oil under the car. If it is looking oil then look where its coming from. Most likely where the oil is leaking, that is what is broke. But somethimes its not. Good luck to ya!