- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
You better find a different mechanic . Before calling a bad fuel pump ,did he do fuel pressure test ? Did he test the electrical circuit ? Did he check mass air flow sensor ,injectors , fuel regulator , engine senors ? How many miles on the vehicle , is the engine in good shape ? Timing chain ?
If you replaced the starter & the car starts the starter is good. The reason when it will not stay crank could be multiple things. It could be your fuel pump, dirty fuel filter, bad plugs or wires, etc... See if you are getting fuel to your carburetor or check your fuel pressure. I'm leaning towards the fuel pump . I hope this maybe some help to you.
If you have already replaced the fuel filter, measure the fuel pressure at the fuel rail. It should be around 35-40 psi when running. If it is not in this range, consider replacing the fuel pressure regulator.
you say fuel pressure is good, but what is it? what is the fuel pressure when it stalls out? Spec is 60-66 psi and it wont run if its 55 psi. the fuel pump relay should be good if the pump runs. Make sure the ground for the pump is good , G402 should be on left frame rail. you may have had it off to replace the pump? maybe? it may be time to stop guessing and have a repair shop diagnose it for you. You sure have replaced a lot of good parts.
did you install the oil pressure switch origional to the tahoe? The tahoe uses a low oil pressure shutdown, instead of an inertia switch to shut off the fuel pump in the event of an accident. If the pressure circuit does not close within 3 seconds after the engine starts the fuel pump shuts off. This is in case the truck is on its side or upside down the pump will shut off.
MAKE YOU HEAR FUEL PUMP RUNNING WHEN TURN ON IGNITION KEY. IF NOT CHECK FUSE AND RELAY.IF YOU HEAR PUMP RUNNING. CHECK FUEL PRESSURE.IT SHOULD 36 TO 40 PSI.IF NOT REPLACE FUEL FILTER.IF FUEL PRESSURE IS STILL LOW FUEL PUMP IS BAD.
In reply: if its not the maf there are 2 relays in the relay box i belive its underhood, 1 primes the fuelline to 32psi the second kicks in after it starts, and keeps it running and varies the psi. if the primer relay isnt kicking in then it wont start due to no fuel