Died won't restart

1988 Chevy 2500 4x4 with 5.7 A/T Engine died while driving no spark no fuel pulse. I can make the fuel pump run by jumpering fuel pump relay but without spark- no run. If ignition module goes will it also kill fuel pump control? The Green wire at fuel pump relay has no voltage when key is turned on or when engine is cranking. I have checked all the fuses all are good. Any ideas greatly appreciated!!!

Thanks, David

Reply to
Acura God
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When cranking, the PCM must receive reference pulses from the module before it will pulse the injectors.

It doesn't matter if you jump the fuel pump....no spark, no fuel from the injectors.

You need to test for spark with a spark tester or inductive timing light.

Reply to
News Skimmer

Ok that did answer my question. I did check for spark but had no spark tester handy so I just grabbed the coil wire as I suspected no spark anyway. It does kind of look like it is gonna be the module bad but as you can tell from my sig-- I am an Acura tech and have thrown everything out the window I remembered from GM school. I have checked G107 and G108 both of which are good and I do have voltage at the ECM where I should have it. I am probably just overthinking this thing and I should just go out and get an ignition module for it and just fix the damn thing!!! Thanks for the help!!!

Reply to
Acura God

anyway. I remember another post about something to do with the control module needing a pulse from an oil sending unit ... to protect from low oil pressure? not sure but if ign module doesnt work it may be worth looking into...really not sure...but thouhgt Id bring up just incase it helps...

Reply to
NOELBIKER

My 89 had run well with the oil sending unit unplugged, but the pressure was pegged out. The issue is most likely that damn ignition module. BD

Reply to
Black Dog

How are you testing if the fuel pump is running or not running?

And have you sprayed any ether into the TB while cranking?

Reply to
News Skimmer

I think you were reading an abominable message about the oil pressure switch.

The oil pressure switch only provides another vote for the pump to run. Disconnecting it will not stop the pump providing the balance of the system is working properly.

So, from memory, the pump will run under any of the following conditions....

1: For two seconds after the ignition switch is turned to the run position provided that it was just off for at least ten seconds 2: Any time the ignition switch is in the crank/start position 3: Any time the ignition switch is in the run position AND reference pulses are being received 4: Any time the oil pressure is 4 psi or higher

There is also a test port in the obd connector to bypass the relay and run the pump provided the relay is not arced/welded closed.

If I left any off, please add to the list.

skimmer

Reply to
News Skimmer

while your at it, you might want to pull the dist. out and put a new pick up in it. the pick up coil is useally corrodedand no signal from the pick up will give no pulse or spark. better that 60% of the time the module MAY give spark OR pulse but the pick up will give you nothing at all.

Reply to
redeye-racing

Exactly the same thing happened to my 95 Silverado....Fix was the Electronic Ignition Switch...About 400 bucks installed at the shop...

Reply to
benick

electronic ignition switch? or module?

The ignition switch is usually not referred to as electronic.

Reply to
News Skimmer

If it is the switch it is not expensive to replace if you do it yourself and the ingition switch itself snaps on to base of housing key goes into so you can replace it easily without replacing everything. I am not convinced it is the cause here though.

----------------- TheSnoMan.com

Reply to
SnoMan

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