4.0l Runs Rough
 

I have a 1991 Cherokee with a 95 Grand Cherokee 4.0l Motor. I have replaced Spark plugs, Wires, Cap, Rotor, and Temp Sensor. It Misses and idles Rough. What could be the problem? I am not sure what else to try. Got any Ideas?:dunno:

FUEL.

IAC or vacuum leak??

I have also replaced the fuel filter... Not sure what is wrong... could be map sensor? It almost seems like a timing issue as well. I am lost. It could be a vacuum leak i suppose. Where do you think i should start?

Run some seafoam in your fuel tank. Also, run some good fuel. Mine runs rough on everything, even 87 with seafoam in the tank, but if I run 91 octane with 0 ethanol, it runs smooth. Try to find a station near you that sells E0 fuel (there is one here, and its 10 miles out of town)

X2 on the ethenol free gas

Really? You that that is all it is? Hmmmmmmm. I did not think it was going to be that simple. I will try that and see if that works. I am willing to try anything at this point to get it to run right. Do you guys know where i can get something online that will explain how to change the transfer case chain? I am kinda nervous about doing it. It will be the first time attacking something like that. :huh: