04 sunfire fuel issue? Possibly*

[adetz08]

Ill do my best to give all relevant information. Im not super mechanically inclined so bear with me.

I have a 2.2 4 cylinder with 87xxx miles. I bought this car about a year and a half ago. Around 6 months the fuel gauge stopped working properly. When i would fill up it would read WAY over full, but would return to accurate levels when the tank was about half full. It also stopped firing up as easy.

About 3 months after that the car died on me while driving. I didnt hear the fuel pump and tried a new fuse and still got nothing. Had it towed into a shop, shared my suspicions that the fuel pump was bad, asked them to diagnose and fix it.

Shop confirmed it needed a new fuel pump, replaced it and I was on my way. At this point I thought the fuel gauge would read correctly but it didnt, and shortly after it got worse. The gauge currently reads past full and almost al the way around the empty again. After i got it home I replaced the fuel filter within a week.

Fast forward to last week. I was driving in town around a roundabout and the car dies. I let it roll to the side, put it in park turned the key off and back on and i fires up and i make it home. Today i pull into a parking lot to take a phone call, shut car of for about 5 mins, start it up, engine fires up for a second and dies. key is at the on position. Turn key off and try it again and no problem. Since the fuel pump was replaced till now ive probably only put about 2k miles on it as i havent been working.

Any ideas what might be going on? Im skeptical if the shop did everything they said they did but i dont have the knowledge myself to say anything. Also for all I know this could be a completely unrelated issue. I start a new job next week and am worried my car is going to die on me. Any help is greatly appreciated. Thanks

 

[melsg5]

Since this is an intermittent problem it is difficult to diagnose.
The pump relay could be failing or even the new pump or something unrelated to the fuel system such as ignition.

 

[adetz08]

I switched the relay with AC relay since they are same size. Didnt make a difference

I also pulled out the spare tire and it seems they cut out a spot for the fuel pump instead of dropping the tank. Makes sense since there quote was significantly cheaper than anywhere else. It looks like they patched the hole with some sort of black rubbery material. im guessing i could cut that and examine the pump to make sure everything is hooked up proper? If i do this is there anything i need to be careful for or worry about? Do i need to replace that cover over the pump with something? Heres a picture of what im talking about

https://imgur.com/lNOvu8F

 

[melsg5]

So is this problem all the time now or intermittent?
When you turn the key from off to run do you hear the fuel pump run for a few seconds?
Can you pull the rubber plug off without damaging it?

______________________________

 

[adetz08]

its intermittent. Yeah i can hear the pump. no the rubber plug wont come off, I'm thinking about cutting it out so i can get to it. If i do that do i need i would need to find a way to put it back in wouldnt I? I have a new theory that the shop just replaced the fuel pump and not the sending unit.

 

[92 Sunbird LE]

Thats a factory water drain plug in the spare tire area, not a axcess to the fuel pump.

Axcess to the pump would be ( if one ) would be under the back seat. Looks like you have to drop the tank from underneath just like any other GM JBody...check YouTube.

And yes , you can change just the pump without changing the module which holds both the pump and sending unit.( cheaper)

You could have corrosion to the wires to the tank or a security computer problem, or bad ignition switch.

Doug in P.R.