Could be your throttle position sensor. When I had one go bad it would almost feel like it's shifting between 3rd and 4th gear when I was at cruising speed.

 

Replaced with a new one long time ago. I went to the local dealer and talk to the guy who has been a tech there for 35 years. He told me its the distributor. Apparently there is a 25 year old tsb that shows how to reindex the distributor. Apparently it has to be redrilled. He has a special tool that he made out of an old distribute cap that he uses to reindex the distributor. He gave me an oem original distributor cap and rotor, he todo me it will fix the issue for a short time but it will come back again soon. The issue is that the spark jumps from one cyl to another. At least thats what he told me is happening.

 

Did this ever get fixed. I bought an 89 and it has this same issue.

 

Pretty sure found the issue. There was a tsb out for 1988 Cherokee. The issue was that the distributor was not indexed correctly. The solution, short is to cut of the mounting tab, cut a window in the old distributor cap and reindex the distributor using a ruler of some sort. Pm me your email and I will send you the tsb.

 

mine did the same thing so i changed the crank senser ...and now it runs great

 

So Im pretty mechanically inclined but I really dont understand what re-indexing is. Is that like resetting the distributer for timing? Is there an aftermarket fix. I hate reoccuring problems.

 

Reindexing is a permanent fix. The issue is than jeeps from the factory came with incorrectly indexed distributor. The only other fix would be to get a distributor that has been manufactured properly with the hold down tab in the right place.

 

I just had my motor rebuilt and they put a new distributer in and it pulls 1391 code it sounds like this indexing problem you had Can you email me your solution . Thanks Ken

 

Could you send me the tsp I just had my motor rebuilt with a new distributer and having problems this sound like the problem. They want to put a new computer .i think this sound s more realistic. Thanks ken allaboutplumbingatl@gmail.com