97 Blazer LT starting issues so far

[mbwchvy]

Hello all,
I've done some searching on previous threads re: my starting issues.
Sounds like the starter switch can be a problem with my year. I believe I have it narrowed down to either the fuel pump assembly or the starter switch. It looks more and more like an electrical problem. When it does start, everything runs great, normal idle, excellent accelleration etc>
Just wanted some extra feedback on what I've found so far.
It cranks over but will not fire up. I know when it's going to fail because then I don't hear the fuel pump whirring (engaging) at these times.
My voltage at the battery posts is 12.6V Also had a load test performed on the battery. I also have "The Protector" alarm system (instlalled when vehicle was new) that has a remote starter built in. When I use the remote starter it performs the same way as using the key. Turns over, just no start.

1)Does this remote starter process, bypass the starter switch theory?

2) Does the fuel pump test bypass lead that you apply to 12V bypass all other circuitry? Should the fuel pump whir everytime voltage is applied? My case no.

3) The bank of relays in the glove box. Which one is actually for the fuel pump? I've rotated them since their all the same. But to no avail, no change.
I've replaced the fuel filter, but have had no luck starting since, to even get the fuel pressure back up.

If I start with replacing the starter switch, do I need to pull the steering wheel?
Any ideas anyone on what I might check next.
Thanks

[ricksza]

The fuel pump prime connector is a direct feed to the pump through the fuel pump relay. If the fuel pump doesn't run, the engine will crank and not start. I wouldn't worry about the ignition switch until I got the fuel pump straightened out. Sounds like either a bad pump or a bad connection.

[mbwchvy]

ricksza
thanks for responding. So what your saying is the prime (red test lead) goes thru the relay first then back to pump? Which relay out of the three is the fuel pump. I hear one of them clicking when I turn the ignition. Just can't isolate which one it is.

[blazee]

I believe it is the middle one.

[mbwchvy]

blazee

Thanks alot for the schematic. I'm going to diagnose this weekend.

[mbwchvy]

ricksza, blazee

found out that 1st relay in the bank of three was the fuel pump (verified by continuity check).
Relay is N.C. on the primer test lead when not energized.
Applied 12V to the lead and no sound from pump at all.
Now I'll have to drop the tank to check the pump and/or it's wiring.
Thanks, I'll keep you guys posted.

[ponchonutty]

Had a simular problem on this guy's 98 Tahoe. No one wanted to touch it because they blamed the remote starter. I told him that I could fix it no matter what it was. Turned out that he'd changed the fuelpump a while back. When putting things together, he stretched the wires that go to the plug for the fuelpump. Well, he pulled the ground lead out of the plug. I repaired the plug and all was fine.

[mbwchvy]

Thanks to all for your help - It was the fuel pump all along. Wiring all checked out good through ohm, and voltage tests.
Thanks again.

[blazee]

I glad you got it fixed. Thanks for coming back and telling everyone what the problem was, there are way too many threads on here with no solution.