bad fuel pump?

[aar0s]

heres what the car does, starts and drives fine for a bit then will start cutting out at high (above 4k) rpms then gets till its cutting out at lower rpm's till it dies and wont hardly restart. No check engine light.
It sat for several months with about a 1/4 tank of gas and at first i just thought the gas was bad and added some fresh to it but it didnt seem to help. could the pump be on its way out or do i have some real skunky gas that i need to get out of it or is there something else going on?
the car is an 01 gt.

 

[wmburns]

Could be:

bad gas.
Clogged fuel filter.
bad fuel pump.
Bad fuel pressure sensor (esp if on a boosted application).
fouled fuel injectors.
Fouled/dirty/weak spark plugs or other ignition problem
Moisture in the spark plug wells.

It could also be a number of other things.

Best to start by changing the fuel filter. Next perform a fuel pressure test (got to start somewhere). Monitor with an ODB2 scanner or an external fuel guage. Post the results.

Good luck.

 

[Flghtmstr1]

It could always be bad gas, but I'd replace the fuel filter before worrying about the pump. It's cheap, and it's always good to have a fresh one in there for peace of mind.

 

[aar0s]

probably should have mentioned that I've already changed the fuel filter. When I push the schrader valve in how much fuel should spurt? not much is...maybe a thimble full. I though about bad injectors, but wouldn't that throw a check engine light?

 

[wmburns]

Motor Gasoline is a un-compressable liquid. As such, the volume of gas will not be that large before FP is near zero. This is NOT a good method to guage fuel pressure.

Besides, we need to know what the fuel pressure is while under a load.

Drity clogged fuel injectors may not throw a DTC unless it is SO bad as to cause chronic misfires.

If you suspect fuel injectors, try an injector cleaning/flow testing service such as injectorrx.com. Much cheaper than new and once tested, the injectors are as good as new.

If you were to ask me to handicap this, my vote is fuel pump. But I am the kind of guy that really dislikes throwing parts at a problem. Instead, test first and then repair.

 

[Cherry99GTvert]

+ 1 Fuel Pump, but yes get the fuel pressure tested make sure its not the relay or somthing even simpler than having to spend an hour dropping the tank.