Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
Hello, my name is John.
The Mass Air Flow Sensor is in the 'accordian' looking tube that runs from the air filter housing to the engine. It is near the end closest to the air filter housing. 5 wires come out of the side of the sensor.
This description is for a 4.2 liter engine, let me know if you have a 5.3. Basically the same but just want to make sure I am looking at the correct engine.
Still could be fuel pump. I have seen GM fuel pumps fail in every way possible including fuel pressure just a few pounds low causing problems like this. I would check fuel pressure with a gauge and see what is is exactly. If you give me the engine size I will give you the pressure spec.
Fuel pressure spec is 48-54psi. If you check it when you turn the key on it should be at the higher end of that (engine running would drop the pressure a little).
Just following up to see what you found out. If you have found the information I have provided to be helpful, please provide a positive rating for my answer.