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American Motors/1979 cj7 4.2l auto- not firing

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Question
bit on the cusp of 1979 limits!

i've got a 1979 cj7 that was working fine starting etc until onday it didn't! it turns over fine but never fires. at this time the circiut with the cigg lighter- radio- electric fuel pump stopped as well. i've tried the electronic ignition box no change, and checked all the normal fuses etc...just wondered if you had any possible tips/ things to try?

Answer
George,
Using a test light, turn the key to the run position. You should have power to the (+) side of the coil. During cranking, the bulb should pulse on the (-) side of the coil. If you have power at both places, remove the coil wire from the distributor cap and hold it 1/2" from the engine block while cranking, you should have a strong spark. If not, check the coil wire for an open or replace the coil.
No power to the (+) side means that you have an open between the battery, ignition switch and coil. For a TEMPORARY fix, try running a wire from the battery (+) to the coil (+) and try cranking it. DON'T leave this wire in place too long.
No flashing light while cranking at the (-) side means you have a defective pick up in the distributor, a bad coil, or ignition box.
I would also check the circuit your electric fuel pump is on. Find out why you don't have power there or why you are blowing the fuse.
Good luck
Kevin

American Motors

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Kevin Pilotte

Expertise

I can answer many technical questions relating to AMC vehicles prior to 1979. I also have experience with Rambler & Nash vehicles.

Experience

I am a former AMC technician, service writer and service manager. I have worked in AMC dealers in Illinois in the 70's. After college, I was a Field Service Rep for American Motors Sales Corporation, working out of the Chicago Zone office. I traveled to AMC dealers assisting in the diagnosis and repair of AMC vehicles. I was also the Area Training Manager for DeLorean Motor Company. I have 10+ years as an Automotive Instructor. I have modified and restored
numerous AMC vehicles. I have been working on AMC vehicles for over 30 years.

Organizations
I have been an ASE Certified Master Technician since 1975. This includes L1. I am also currently a Toyota Certified Master Diagnostic Technician.

Publications
I have articles in "American Motoring", the official publication of the American Motors Owners Association. They are the largest AMC club in the world.

Education/Credentials
I have a certificate I printed out from a website.

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