87 XJ Jerking during accelleration, hard starting and stalling???

[XJ_Matt]

My 86 XJ was doing this same jerking with only 350miles on the new engine, but its a GM 3.4L carbed motor. It was getting worse and more frequent. After 400 miles it was misfiring bad and i found no spark on one clyinder. The Jeep mechanic recommended champion plugs. One had gone bad, like melted the elctrode and was bridged due to not firing. I then changed all the wires, went to autolite plugs and distributor cap/rotor. The problem hasent since come back. Champion plugs suck, all i got to say.

Matt

 

[jneary]

champion plugs work great on the amc based powertrains. on the v-6 ac delco plugs work fine.

 

[csr_011]

These problems started popping up about a year after the rebuild. I ran like a champ and got about 25 mpg on the hwy for the first 2500 miles. i havent checked the dstributor index and yes there is a slight hissing when the brakes are applied. I am also thinking that maybe there is junk in the tank, wont be able to do anything about that till next weekend though.
Thanks,
Cory