Hi, I have a 1994 chevy silverado 1500 with a 350 engine and its 4-wd. When I push on the gas peddle barely and hold it there it will act like it is starving for gas and when I let off of the gas the RMP's go really low and it acts like it wants to quit but doesn't and the RPM's will go up to normal. I've changed the O2 sensor and TPS sensor and it's still doing it?

Thanks

 

maybe you are right...maybe it is fuel starved. Have you checked the fuel pressure?

 

Try cleaning the throttle body firs and see if your situation improves.

Cleaning a Throttle Body | The Family Handyman

 

I haven't checked the fuel pressure yet. I've cleaned the throttle body but it didn't seem to help.

 

It also only does it when the vehicle is warmed up.

 

IF it wasn't for your warm engine only scenario I would say it is a fuel filter. Fuel can pass through a dirty filter to allow an idle with no problem. Go WOT and not enough fuel can pass through, starving the engine of fuel...no power.
But this should be the same regardless of engine temp. Almost sounds like you are getting some type of vapor lock on a warm engine.
Dumb question...does it do it on a full tank of fuel as well as a quarter or less?

 

Ya it does it still does it with a full tank or a quarter or less.

Thanks

 

that probably rules out an overheating fuel pump. Full fuel tank usually keeps the pump running nice and cool.

 

Ya its been doing it for a long time. Could it be a sensor?

 

I've cleaned the EGR valve too.