1999 Chevy Suburban V8 Four Wheel Drive Automatic 180000 miles
I have a 1999 Suburban, 5.7L V8, 4WD that will not start. A little background: last year the Suburban would not start one day. I noticed I could not hear the normally noisy fuel pump when the ignition was on. Checked fuses, fuel pump relay, seemed OK. Had it towed and they replaced the fuel pump. Worked fine for a month, then just would not start again one day. Seemed like the same problem. After fuel pressure test showed only 40psi, fuel pump replaced again, with GM unit. Then a couple days later, it just died while driving. Replacing the fuel pump relay took care of it (although it seemed odd at the time). It's been fine for a year.
Today it would not start, and again when then ignition is on I don't hear the fuel pump, which I believe I should. Bench tested two different fuel pump relays (have a spare) and both are fine, I can hear and feel them actuate. I expected to hear/feel a click when plugging the relay into the socket (with the ignition on) but nothing happens. Checked the voltage for the relay coil at the socket vs. Gnd, 12.9V. Left the voltmeter on the relay coil pin, then connected the relay (using a piece of wire) and the voltage dropped off to almost nothing. The other relay coil wire was connected to chassis gnd. (I did not check the + coil voltage vs. The other coil pin with the relay connected, only referenced to gnd). I have wiring diagrams from a Hayes manual ("typical 1996 and up") which show a fuel pump relay, as well as fuel pump balance relay. This is confusing me a bit.
Also, there is only one wiring connector that I can see which goes up to the area above the fuel tank/pump area. It's a 2-wire connector. I do not get any voltage vs. Gnd on either of the wires. I assumed 1 of these wires is for the level sensor and the other for the pump motor, but I am not sure. I don't know if I'm on the right track, or what to look at next. Help is appreciated!
have the same problem?
Tuesday, November 24th, 2009 AT 11:56 PM