Searched for this and couldnt' seem to find an answer that pertains to grand cherokees...

The jeep is a '94 grand with the 5.2 v8. It has 287k, and about 10k ago it had the rear main, timing belt, water pump, and engine mount replaced, as well as cap, plugs, wires, and rotor. (there were some other things, like the trans kickdown cable, oil sender, etc, but these dont really matter)

Before the new parts, the engine would lug down or lope on startup, especially when warm, and would level out after a few minutes.

Its better now but still occasionally lopes at startup when warm, even as the weather is cooling (this is why I'm not thinking its hot fuel/injectors, as the temp has changed but the symptoms haven't)

Anyone have this problem or solutions? It does sound sort of like the hot #3 injector issue some 4L have, but like I said I don't think that's it, nor would I know of a solution for it if it is, the engine geometry is totally different so there's not a hot spot from the exhaust to cause that issue.

There doesn't seem to be any fuel consumption issues (gets about 16-20, depending on the day (lots of varying highway/city driving)), but engine almost dies with this unless you rev it up a little. It does rarely die putting it in gear (auto).

 

crank sensor fixed mine, itwas a 94 grand with a 5.2. Guess when the sensor got hot it would heat soak until you move a little.

 

Thanks! I'll try that. Where is it located? I'm only familiar with the CPS on the I6 in the XJ.

 

more of a pain on the 5.2 If u are standing in frontof the jeep, it is slighly left, and is easier to remove the egr valve to get to it. You CANT see it,no matter what, unless you have a mirror. funny thing was, I didn't think it would fix the loping idle after warm start up, I was having a issue that it would die when hot out, so figured it should be replaced, to attempt to fix the problem. Well it fixed alot more then I thought it would!!