dv3408

I have a 96 grand cherokee limited:
4.0L
233k miles
On most days this possesed vehicle will start up and idle for 5 mins give or take depending on its mood and stall, after that its almost impossible to start again. It will also stall at junctions and misfire.
Advance auto ran the codes and it said multiple misfire and reported misfires on all six cylinders. I've only had it for a little over 2 weeks and the first week the thing drove like it was brand new! Shoot me some ideas! So far I've replaced: IAC valve, temp sensor, distributor (entirely), and plugs/wires. I'm at a loss

jeep_colorado

My 96 grand had multiple misfires on all cylinders and turned out to be i installed cheap plugs i bought new, top of the line plugs and she ran like a champ afterwards. But mine never stalled and would always start. Did you install cheap plugs? if so that is most likely the issue. took me weeks to figure it out. I would also recommend pulling your alternator and get it tested.

dv3408

The plugs were chenged before I got it. I pulled a couple and checked the gap and it was .35 as it should be but the plugs have no branding so with that said its likely they are cheap ones. I also have a new battery and terminals and the alternator looks news as well ( no buildup or dirt). I had to have it towed the the lot I got it from which also has a garage. But as soon as it came off the truck it started and ran for 15-20 mins with no problems,they kept it all day starting it and letting it idle and stopping to let it cool down over and over and found no problems. I picked it up and drove it to dinner and home with no problems. The next morning no start again! The fuel pressure checked out around 50psi so no prblems there

jeep_colorado

You could possibly have a clogged fuel line, I dont know much about that tho. but a clogged line would show correct psi when jeep isnt running. Other than that i have no clue, bad plugs would do it all the time. good luck and hope you get it fixed soon!

Bustedback

Sounds like you have a fuel pump problem. Check the pressure with a gauge hooked to the fuel rail, the spec is 44-56psi.

dv3408

As I mention before the fuel pressure checked out fine at 50psi. Ove the past couple days I took the throttle body off and was able to adjust the low idle. I cleaned and re gapped all the plugs till I get new ones. I drove it today for the first time since all of that and haven't had the first problem. 233k and still running like a tank lol. Thanks for the suggestions!