Will not stay running

BIGAL55

MEMBER
1981 JEEP CJ7
4.2L
6 CYL
4WD
MANUAL
170,000 MILES

I have an 88 yj that I bought recently, it has a replacement engine that I believe is from an 81 cj it has an offenhauser intake and a Holley 390.

I was driving down the road the other day and it cut off. Wouldn’t start back up immediately but then I got it started and drove home. Now it will only run for a couple seconds and then will shut off.

I am getting plenty of fuel to the carburetor, took off both bowls and the floats are functioning properly and I replaced the needle and seats.

I replaced the coil and spark plugs and the distributor seems to be in good shape, (clean and rotor does not have play).

I do not know what is wrong, I am thinking it is a carburetor issue or vacuum perhaps. Please help.

3 Replies

ASEMASTER6371

MECHANIC
52,797 POSTS

Good morning,

I would take a voltmeter and make sure you have voltage at the positive side of the coil with the key in the on position. Keep it on it when it starts and see if the signal or voltage drops out. It sounds like you are losing spark here.

https://www.2carpros.com/articles/how-to-test-an-ignition-system

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-use-a-voltmeter

If it drops out, then it could be the ignition switch. This needs to be confirmed.

If it does not then it could be the coil or the module.

Roy

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