I have a 2002 Sunfire 2.2L. A few weeks ago my car had problems starting, it would turn over and I could hear the fuel pump engage but it wouldn't start. Occassionally I would get it to start but the second you turned it off again, it wont. I replaced the fuel pump and that is not it. Now when I put the key into the ignition and turn it I get this humming clicking sound from the fuel pump relay. I also replaced the battery, and the sparkplug wires but still didn't fix the problem. Please help!

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When you replaced the fuel pump, did you disconnect the battery? If you did, did you reset the security system and engine immobilizer?

have the fuel pressure and volume tested with a gage.this sounds and acts like a fuel pump problem.check the fuel filter as well and replace anyways.when it won`t start but cranks can you hear the fuel pump running.listen at the fuel filler neck with the gas cap off.if you can`t listen under the car at the fuel tank you should hear it running/if not hit the gas tank and if the car starts then the pump needs replacing.you should check to make sure you are getting spark at the spark plugs to eliminate an ignition problem but i think its fuel.

depending on your knowledge of the vehicle check the crankshaft sensor, and the fuel pump relay. see in you are getting spark to the plugs.

sounds like fuel pump just cause you hear it does not mean its good, 1st thing check for plugged fuel filter

Have somebody listen at the gas cap for a buzzing sound when the ignition switch is turned on, or if you can hear it, it only does it for a few seconds, if you don't hear it, the pump is bad and the gas tank has to be dropped to change it.
This is not recomended, but I do it all the time to make sure the problem is in the fuel system. Spray a little bit of starting fluid in the intake, if it starts, the problem is in the fuel system, but listen for the buzz sound first.
Other problem could be a clogged fuel filter, or a faulty fuel pressure regulator. Have a fuel pressure test done, that would also reveal the problem, if it's a fuel problem.

The fuel filter is in the hood (metalic black) and the fuel pump is in the fuel tank (either through the back seat or bringing the tank down.

Cheers

yes you can first change the fuel filter and also have the fuel presure checked if still no luck have fuel line checked for blockage

sounds like the fuel filter.. if you have those kind of skills, they're usually cheap to buy and worth a shot to change. depending on the location the labor will take you 1 - 5 hrs...

First listen for the fuel pump. when you turn the ignition to "on" , just before start, you should hear the fuel pump whining. What you need to do is remove the fuel line going into your fuel rail. Get a small container and turn the pump on and off a few times to get some of that bad gas out. Reconnect fuel line and see if that works. If that doesnt work, Next would be to change the fuel filter which is just behind the rear axle. Other than that you could drain all of the fuel by disconnecting the fuel line to the filter and let it all drain. I dont see a lot of water getting into your port just by leaving the cap off. You might have bought bad gas.

is that at 100 miles an hr ? if so does the car have a rev elmitor on it .?