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Discussion Starter #1
Tried to do some improvements to my 88 with 4.2L and something isn't right! Pardon the long email, here is the deal:

1. started by putting a 34 dgec weber on it years ago. This helped but it still ran a little rough and rich (pumped out a little over 5K hydrocarbons at deq)

2. Did nutter bypass. This smoothed it out a ton
-with that I reset the timing (@10 with vacuum off) and re-set the fuel mixture
*at this point I could start it up and let id idle up to temp., then take it for some hot laps. It would run OK until it was between 2500-300 rpms then start sputtering out.

3. So, I added a fuel pressure regulator and filter and set it to 3.5
-Noticed absolutely no difference

4. Tried cleaning out the jets by spraying carb cleaner through them
-Still have the same problem...

Now it starts up and idles fine, then I take it for some hot laps and it starts sputtering past 2500 rpms. THEN if I let it sit at idle after taking it for test drive, a few minutes later it starts sputtering out and at idle and running like complete crap - then dies shortly after. Then I let it sit a while, and it starts up and idles fine.

Does this sound like it could be the timing and maybe I screwed up along the line? Or the fuel mixture? These are the only two things I can think of.

Please help! Need to have it reliable for hunting season. :surrender:

I cannot find any vacuum leaks and I do not have a cat on it.
 

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Discussion Starter #3
Plugs and wires are about 3 months old but the coil could be old, I don't remember ever replacing it. Could a coil be causing this...maybe if it gets hot?!
 

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Discussion Starter #5
Mr. Mud. You are the man. Jeep fixed with new coil...my Dad suggested I check the coil too and now she runs like a Swiss watch. Its never ran this good before. Nice call if we ever cross paths I am buying you a cold one.
 
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