97 Z28. Crank no start. Check here and find a thread about fuel pumps...
Is the fuel pump running?
No.
Fuel pump not running. Can it run by bypassing using the little pigtail off the harness under the hood?
Yes! Weird eh?
Certainly it's the relay or fuse.
All fuses are fine. Contacts are good. Fuel pump relay is under the GD left foot rest, so remove that plastic panel with 5 screws.
Relay no click. Surely it's the relay. Pull relay and test by connecting an old headlight off my Austin Healey Sprite.
Hot to headlight on pin 30.
Headlight switch to pin 86.
Chassis ground to pin 85.
Hot from battery to pin 87.
Headlight ground to ground.
Touch from pin 86 to battery positive and relay clicks, headlight turns on.
Relay is fine?
How about the wires themselves?
Turn on key and test voltage.
Is the relay seeing voltage from the computer or battery?
See 12v on the wire to pin 87. So yes. But that only actuates if the relay trips on, which is controlled by the computer tell it to on pin 86. Which has no volts.
So the computer isn't telling the relay to trigger. But the car runs fine if you supply 12v to pin 86 yourself, or bypass the relay entirely.
Where's the computer?
Look behind computer, see mouse nest...
Wound up having a buddy volunteer to jam his tiny hands in there (we did unclip the wiring harness from the body mounts and move the mess enough to strip and reconnect the wires).
Once the green (IIRC) was reconnected, the car started fine.
This car is driven quite often, but somehow the mouses ate inches off four wires.
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Is the fuel pump running?
No.
Fuel pump not running. Can it run by bypassing using the little pigtail off the harness under the hood?
Yes! Weird eh?
Certainly it's the relay or fuse.
All fuses are fine. Contacts are good. Fuel pump relay is under the GD left foot rest, so remove that plastic panel with 5 screws.
Relay no click. Surely it's the relay. Pull relay and test by connecting an old headlight off my Austin Healey Sprite.
Hot to headlight on pin 30.
Headlight switch to pin 86.
Chassis ground to pin 85.
Hot from battery to pin 87.
Headlight ground to ground.
Touch from pin 86 to battery positive and relay clicks, headlight turns on.
Relay is fine?
How about the wires themselves?
Turn on key and test voltage.
Is the relay seeing voltage from the computer or battery?
See 12v on the wire to pin 87. So yes. But that only actuates if the relay trips on, which is controlled by the computer tell it to on pin 86. Which has no volts.
So the computer isn't telling the relay to trigger. But the car runs fine if you supply 12v to pin 86 yourself, or bypass the relay entirely.
Where's the computer?
Look behind computer, see mouse nest...
Wound up having a buddy volunteer to jam his tiny hands in there (we did unclip the wiring harness from the body mounts and move the mess enough to strip and reconnect the wires).
Once the green (IIRC) was reconnected, the car started fine.
This car is driven quite often, but somehow the mouses ate inches off four wires.
