95 astro vin w no power to fuel relay- wont start

[ozone]

yup, i'm a newbie. been reading threads all day!

several days ago i was driving and the engine quit. no sputter, just died. i tried to start, but no go. i put the key in run position and checked for fuel pump sound. it was running and running, and running! it would not shut off as usual. i checked for leaks, but found none. i tried to start again, and she fired right up and i drove about 10 miles home.

today, i went to start it, and nothing! fuel pump did not run. i switched the fuel pump relay with the one next it, but same problem. i jumped the fuel pump relay and the pump ran. i let it run and tried starting, but no go.i sprayed fuel in the intake and it fired. seems there is no power to the fuel pump relay.

i don't know if the problem the other day is related or not. i don't have a fuel pressure gauge, but will try to get my hands on one this weekend. the fuel pump and filter were replaced last fall, and only have couple thousand miles on them.

would a bad fuel pressure regulator cause this problem? does the regulator turn the pump relay on and off? if the fuel pressure is good, should the injectors fire when i jump the relay and let the pump run?

any thoughts? sorry for rambling .... my brain hurts!

[ozone]

update,

got the fuel pressure tester and the pump puts out 62psi when i jump the relay. after 1/2 hour, its still holding 53psi.

i guess i will pull off the plenum cover and see what i can see. i'm still wondering if a bad pressure regulator would disable the pump priming cycle on start up and cause the other problem i had initially.

any thoughts are welcome!

[NotDadsW41]

Pump is fine with that pressure. Sounds like there is a short between the relay and the pump if you can swap relay and it still doesn't work...

[skippy]

The grey wire from the relay is your power wire from the relay to the pump , check it for power when you turn the key on . it will only show power for less than a minute till the van starts then you'll have constant power on it while its running . i'm thinking you have a bad relay , just swapping them out is not going to work because i believe the one next to it is for the blower motor & a different relay , so its not going to work for the pump . get a new relay thier not to expensive .

[ozone]

thanx for the reply guys!

skippy, the relay next to the fuel pump relay is the idle air solenoid relay on my van, and is the exact same relay.

both, shouldn't the engine start if the pump is running (using the fuel pump pigtail connector) with that pressure?

btw the van has 216K on it, and the ses light did not come on.

i went ahead and took off the plenum today, and noticed that the passenger side is fairly clean and coppery colored whereas the drivers side is super dirty. from what i've read the clean coppery color indicates that there is a fuel leak. i pressurized the fuel system, but see no obvious leaks anywhere on the regulator or injector body.

can the fuel pressure regulator fail in such a way that no fuel gets to the injector?

is there a way to get the injector to fire with the plenum cover off - like by putting a voltage across the 2 injector wires?

i'm wondering if i should just ignore the clean coppery color and put it back together, thinking that whatever is keeping power from the fuel pump relay is also keeping the injector from firing and is not related to the fuel pressure regulator?

i don't wanna throw money at it if i don't have too!

[ozone]

here's the latest,

got a fuel pressure regulator at napa, part number 700-2368 ($45) and installed. put power to the injector, and it sprays fuel, seems to work fine. no leaks anywhere, so i cleaned up the egr and put it all back together.

i removed and cleaned the ground wires on the thermostat stud and the ground wires in back by the fuel line bracket stud, main engine ground, and chassis ground. turned the key to on, and still no fuel pump. went to do something else, and came back to try again. i turned the key to on and whaddaya know, the fuel pump comes on and primes up! i notice that the relay "chatters" as it shuts off. i hit the key and she fires a couple times but no start. there was fuel in the intake from my injector test and some carb cleaner, and i think thats all it had for fuel.

i try again, turn the key to on and no fuel pump again! i jiggle all the wires, nothing. a couple tries later, and the pump primes again! i crank it, but it does not fire. i try several more times, but the pump will not come on again.

this whole time, i have been hitting the key while leaning in from the passenger side door. i go over to the driver side and guess what?! i notice that the ses light does not come on when i turn the key on, nor when i crank it. obviously i have some sort of intermittent problem with the ecm or wiring. the ses light is not coming on, the fuel pump relay gets no juice, and the injector gets no signal.

i'll start tracing wires from the ecm and see if i can find anything. if i can't find anything, i guess i'll take the ecm out and have it tested at a dealership.

anybody have any thoughts?

[LiftedAWDAstro]

Check the ECM fuses for corrosion. Also, is the ECM located in the passenger foot well? If so check the wire harness going through the firewall and dog house. The wire harness will cross over the right valve cover and can short out. Had this happen to a friends 93 Astro.

Next thing to check is to see if you get voltage to the pump when you cycle the key. Do not go by the pump making noise or not. If the pump is intermittent you may or may not hear it. Use a test light or meter to check at the connector just before the gas tank.

[ozone]

hi,

yup, the ecm is in the passenger foot well.

i came across this post:

post:http://answers.yahoo.com/question/index ... 425AArVQ7E

and plan to follow this test procedure today. i'll check the harness and doghouse passthrough also.

i checked the pump power with key on, and there's nothing.

thanx!

[ozone]

problem solved!

i checked the ecm supply voltage at the ecm connector, and noticed it was fluctuating and only got to 7volts at best.

long story short, i had a broken power wire INSIDE the passthrough block just inside the potting compound. luckily the potting compound is clear and i could see some green corrosion. i dug out the wire, and it was totally corroded through.

i spliced it with a new wire and siliconed the passthrough back together. she fired right up and runs great!

thanx for the passthrough tip lifted!

almost ran out of expletives on this one!

[LiftedAWDAstro]

Glad I could help you out!