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Need help with CJ8 ignition

401 Views 1 Reply 0 Participants Last post by  **DONOTDELETE**
I recently installed a new distributor cap and rotor on my 85 CJ8 with 258 motor and Weber carb.

After installation, I started the motor and it ran reasonably well, no missing, etc.. Then after a few seconds, I noticed a voltage drop on my volt meter of about 1 to 1.5 volts. The motor then began to stall and finally died. I restarted and the same scenario happened again.

I'm wondering if the improved spark from the new cap and rotor is causing a hotter spark and affecting the oxygen sensor. Since I have the factory style distributor, I believe the on board computer can still adjust spark, etc in the distributor based on O2 readings. Is this true?

If it is, can I adjust the fuel mixture on my Weber carb to maybe lean or richen the mixture? Am I assuming all this correctly or do I have some other kind of problem now?

I'm kinda stumped here and am thinking about going to the GM HEI ignition change to totally eliminate the computer from the ignition loop.

Any ideas? I could sure use better expertise than mine!


85 CJ8,258,Weber32/36,4" BDS lift,4.10,35"tires,f/r lockers
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You will get better results if you disable the computer when you use a Weber or any other aftermarket carb. The computer just plain won't work right unless it has the original carb with the stepper motors.

I've got an article on the wiring changes needed in the Jeep-tech section of Follow the article, but ignore anything pertaining to the carb. I'm not sure where ported vaccum is on a Weber. You could find it with a vaccum gauge though. You want to hook the distributor up to the port that shows no vaccum at idle but gets increasing vaccum as the throttle is opened.

Drop me an e-mail if you have any questions. [email protected]
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