Motor swap. Now it won't start!

Asked by Guru9V3Z Mar 19, 2017 at 06:07 PM about the 1997 GMC Jimmy 4 Dr SLE 4WD SUV

Question type: Maintenance & Repair

I have a 97 GMC Jimmy I just bought with a blown
motor. I had a 99 Chevy Blazer with a good strong
motor. The 97 was a 4x4 but the 99 was not. We
have the motor in and Everything is hooked up
correctly as far as I know. The Jimmy will turn over
and sometimes starts but will not continue to run,
and runs rough. If I press the accelerator it will die,
it also constantly sounds like it is going to die, like
it's running low on fuel. I have replaced MAP
sensor, spark plugs, fuel pump is good, fuel
pressure is good (60 psi) distributor cap, is there
anything thing else I am missing. I am a mom
about to pull her hair out!!!! I don't have the money
for a mechanic. TIA!!!

70,925

Kelly answered 7 years ago

did you use/ try the computer that came with the 1999 ? > http://www.ecudoctors.com/ecu-fault.html

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61,205

Andrew answered 7 years ago

Don't use the 99 computer, use the 97. Both pcm's should have passkey anti-theft. The 97 pcm would only work with the 97 ignition. The swap should work. Perhaps timing got off a little on the distributor? With the cap off rotate the engine to tdc. There is a little #6 on the distributor about at 9o'clock. When at tdc the rotor should point to it. Make sure the grounds are on that were ment for the 97. Somewhere either 97 or 98 they changed the location of engine grounds. You should have 2 on the back of the head and one on the driver side of the block usually viable form the front.

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