Cranks but No Start

[tccrab]

Originally Posted by green zr 1

Tom, I just installed the correct AC Delco replacement battery and it has side terminals. The previous battery cracked and leaked a little acid on the frame and caused some corrosion which I have meticulously cleaned. In between these problems, the car has started and run perfect a couple of times, but the problem has reoccurred and is now a no start. It has also not been driven on a wet road in six years. All of the positive wire connections to the terminal block have been cleaned thoroughly, but I have not checked the fusable links. I was under the impression based on what I read in the service manual that if I did not have the ses light I could have a bad power connection to the ecm. The car is currently in my garage in Calais, Maine, one mile from the Canadian border, and I am on vacation in Northern Virginia this week. The security light flashes, does not stay on steady, so I have just assumed that it was not the VATS system but nothing would surprise me at this point. I am trying to resolve these problems as soon as possible, so the car can be moved to a much warmer location in the south before there is six feet of snow in front of my garage door. Please keep the ideas coming. Also, the map hose is clear and still connected at both ends and seems to be fine. Thanks. Shannon Walton ZR-1 1990 #1066

Shannon:

OK, it's not the battery.
Power to the ECM comes from fused wire directly from the positive battery terminal.
You'll have to remove the gill panel (the piece that covers the battery on the outside) to get at the fuse. Reach back along side the battery and gently pull out the small wire on the positive battery terminal. There's a fuse about a foot down the wire. This is power to the ECM.
Here's hoping that the fuse is burnt out or has suffered damage from the acid leaking.
If there's no power going to the ECM there's absolutely no way the engine will fire.
Crank, yes.
Start, no.
The ECM controls operation of the fuel injectors, without it, no fuel to the cylinders. I can't say if the fuel pumps would work without an ECM, I'd have to look at the wiring diagrams.
Speaking of fuel pumps, have you checked to see if you've got fuel pressure?
There's a shrader fitting on the passenger side fuel rail, just to the left of the air horn. It has a metal cap that you will have to remove. You can either hook up a fuel pressure gauge there or you can just give it a slight push with a small screwdriver with the key in the "ON" position. Be sure to have a couple of rags handy to catch the gas as it squirts out.
This will tell you if the fuel pumps come on. If you've got no fuel pressure, car won't start either. Fuel pumps go bad, I've seen a few posts about them over the last year and a half that I've been a owner/member.
I'm pretty sure the fuses for the fuel pumps are hidden under the hush panel on the passenger side in a small secondary fuse panel. Why GM saw fit to hide a fuse panel up under there is anybody's guess.
I've read to use the fuel pumps for a Chevy Surburban with a 454 (don't know off hand what year), same as ZR1, about half the price.

I'm pretty good with a map, so it would probably be accurate to say that Calais Maine is probably not just down the street from Sacramento CA.

When you get back to the car, let us know what you find out.
Since your problems sound electrical, be sure to dig out a good Ohm Meter and your Helms books.

Good luck, enjoy your holiday.
Gotta be real pretty in West Virginia right about now. Lots of leaves turning colors. My favorite time of year.

TomC
'90ZR1 #792

[petefias]

First thing I would check is fuel pressure. If pressure is there would see if the pressure holds. Next, check injector resistance.

If the starter cranks than you can rule out VATS.

You may need a service manual...

[tccrab]

Shannon:

Any updates?

What have you learned?

TomC
'90ZR1 #792

[Demps]

If the car starts and runs for a few seconds, then dies-->primary fuel pump has failed. Both run at start up then the secondary turns off. Ted