nabottino

Hey guys I own a 98 grand cherokee, 4.0L v6 engine and just the other day i was driving and the car had literally shut off when i went to accelerate. It cranks but wont turn over. The lights stayed on and I don't think its the battery or alternator. I'm praying it's not the PCM but my father thinks it might be the fuel pump in the tank. Whenever the car was on there was a high pitch noise going on underneath towards the tank. There is some electrical issues with the dashboard and sunroof but i thinks its more with the wiring.

PLEASE HELP not sure what to do and was looking for somewhere to start
Heres the video to see (I restate the problems in video):

watertrucker

You mentioned a noisy fuel pump. That would be a good place to start. Sometimes they will get pretty loud before they quit completely. Remove your gas cap and listen while you have a helper turn on the ignition. If pump is working you will hear it run for a couple seconds. If you don`t hear anything, check fuel pump relay in the PDC undr the hood. If that doesn`t change anything then it`s probably time for a new fuel pump.

dave1123

When you turn on the key, the fuel pump should only run for a few seconds to charge the fuel rail. It doesn't run again until the PCM get a signal from the crankshaft position sensor that the flywheel is actually turning, as in cranking. Is it running constantly anytime the key is on? If yes, do you have fuel pressure?