Jonrogers0760

Hi everyone,
I am having a major problem with my 2001 Chevy Silverado 1500 5.3L/2wd. In hot weather, the fuel pump shuts off and prior to this the alternator discharges. Then battery light comes on. In most cases it will immediately restart, sometimes it runs perfect after a restart, sometimes it barely runs with not enough power to pull itself which requires another restart. The fuel pump seems to go on and off for no reason. We have changed the fuel pump pressure sensor, cleaned and changed the fuel filter about 12 times in the last 3 years, had the throttle body cleaned, new plugs, new plug wires. The part that is driving me crazy is that I have never experienced this problem in the winter. It seems to be a summer only problem. Any advice would be extremely appreciated.

Thanks in advance
Jon

EinST

Welcome to the forum. I'm not sure what you mean by "alternator discharges" but I assume the voltmeter needle drops and then battery indicator comes on in the I/P cluster? All this happen before the engine actually shuts down? How do you know when "the fuel pump shuts off," though?

If I have to take a blind stab at it, it sounds like the ignition switch fault. In those years, a lot of current flowed through the ignition switch which prematurely (well, if 10 years is premature) wore out the electrical contacts.

Jonrogers0760

Hi EinST, thanks for the response. You are correct when you say that the voltmeter needle drops and then the battery light comes on and all this does happen before the engine shuts down. We are on the same page there. As far the fuel pump, I don't hear it anymore when this happens, it has a distinct hum to it. Sometimes almost immediately the fuel pump will come back on and the truck will drive fine. As the blind stab, did you mean that we would have to replace the ignition switch?

A side note I just thought of but didn't include in my original post because I have done a lot with the truck over the years but for the last two or three years (about when this problem started) I've had to jiggle the key up and down in order to turn the truck on. The key became difficult to insert, turn, and start the truck. I figured at that time the switch might be wore, instead of replacing it I had a new key made and it was easier to start so I let it go. Also I am able to remove the key with the motor running and the truck will continue to run.

Thanks for the help so far
Jon

EinST

It does sound like the ignition switch is worn out in which case you'll need a new ignition switch and lock cylinder (rekeyed to existing keys). An automotive locksmith can do all that usually for less than a service department. You may be able to get by lightening the key ring to lessen the stress on the ignition switch for a little while longer. I've always carried my car key separate from the rest of the keys and junk. It's worth the trouble since I'd have my key fob with me even if I happened to get locked out.