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98 GTP Will Not Start, ECM not initalizing fuel pump or Injectors?

G

gzibell

New member
Hey All,

Parked my Grand Prix this winter as I had a different car to drive and the tranny was not cooperating very well. Started it every few weeks until one day it just did not start. Was to cold to work on it so I waited till this spring. Got it fired up one day and took it out for a spin. Parked it next to my garage and now I cannot get it to fire up. The fuel pump will not initialize when turning the key on, so I used a wire to jump the relay and get the fuel pump fired up. Fuel pump ran good, great pressure at the rail. Cranks over but still will not fire, plugs are dry. I shot some starting fluid in the intake to see if that would help and it fired for a second so I know I am getting spark and no fuel.

I tested all of the connection on the fuel pump relay one at a time, connect test equip, key on, watch for light, key off. I got nothing on all but the constant 12v post. So it seems that the ECM is not initializing the fuel pump or the injectors. Thinking that ECM went bad I picked up a different one from a salvage yard to give it a try and nothing changed. So for whatever reason after sitting for 3 months or so without running something happened that is causing the ECM to not start the fuel pump/injectors. Checked all fuses test good, replaced important relays as well.

Any suggestions? Must be a wiring harness that is damaged somewhere and had time to corrode. Any problem areas on this car?
 


With key on, the pcm gives a prime to the injectors and kicks the pump on for a moment to have pressure for said prime.

Crap..I knew this and have forgotten, I don't believe it relies on seeing an ICM to do so.
 
Forgetting sucks. That would be nice to know. Strange thing is my scan tool will not connect to the ecm. I would think if the icm failed that would generate a code but maybe it just breaks it all together. That is a pricy part to throw at it though. Can anyone confirm?


Oh and edit, I do have spark a shot of starting fluid fires it up for a second.
 
Last edited:
SOLVED!!!

Found a orange wire on the ecm that was supposed to be 12 volts constant. It was dead. Ran a new fused line, fired right up.

Amazing that a car with 275k can still smoke tires and lay black for a loooong time.
 
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