[ThatJeepingFamily]

Well new on this forum, I have a 1999 Jeep Cherokee classic 4.0l 4x4 that is driving me nuts. We have came to a dead end on what maybe wrong with it. Looking for other opinions on what might be wrong. So let's start from the beginning....

Thursday 1-12-2023
Jeep ran fine all week. Back and forth to work. Thursday comes get home and try to back up to our building to dropoff some lumber. Jeep shuts off in reverse. Didn't want to run right. Got it moved to a flat spot and it died. Everytime you put it in gear. Shuts off. Flooding out. Couldn't figure out what in the world was going on.

Friday 1-13-2023
Onto the next day, trying to continue figuring out the issue... Ended up burning the starter up. Got a new one. Turns over great. But no fire. Tried a new crankshaft sensor. Had the same issues. Flooding out. No crank. Wasn't getting spark. Went through and looked at sensors and relays. Replaced some that looked bad. Still didn't work. Finally get it to fire up. Sitting in the drive seat, get out. It died. Got back in seat. Fired. Got out. Died again. Searched the seat for a wire maybe. Nothing I could find. Fired it up again. Shut the door. Died. Game of hit and miss. Jeep would idle fine. Sounded good. Put it in gear and it would die over half the time. Give it gas and then let off. It would die.

Saturday 1-14-2023
Got to tinkering on it again. As this is the work vehicle to drive back and forth. Went through issues of no spark coming out of coil. But coil had spark going into it. Put the other crankshaft sensor back on. Got the same results as with a new one. Went through fuses and relays again. Unplugged some door wires, etc. Still not running right. We cleaned the idle air control valve. Changed the throttle body position sensor. Was running good. Better than previous. Then it died again. Flooded out. Wouldn't crank. Got it fired up again. Idled good. Tried to move it. It died. Wouldn't crank.


Now the fun part is we have to do this cycle after it dies every time. We unplug the battery. Then unplug the crankshaft sensor from the wiring harness. Wait a few minutes. Plug everything back up. Jeep will crank first start. Or it will flood itself completely out.


Any ideas? Probably forgot something. But it's been a stressful 3 days trying to get this thing running right again. We have another jeep that's our family vehicle. Seems like I'll have to be driving it till we figure something out with the ol xj.

 

[ThatJeepingFamily]

Hello and welcome to the forum. These Jeeps are notorious for thin wiring and bad grounds. check the grounds on the fender and at the block. Check the wiring that goes behind the valve cover it can rub against a valve cover bolt and short out.

Will try that today. Do you think it could be any other sensors or something?

 

[ThatJeepingFamily]

Fuel pump primes. It's definitely getting gas. When it backfires we have flood smoke come out the air box and hose. We unhooked the doors power windows and lock wires. No longer had this issue. The distributor cap seems fine, we checked that too. We was having power go into the coil pack. But not out. Could not figure that out. When you get the jeep crunk up it will idle as pretty as can be. As soon as you put it in gear or give it a little gas it will shut off. And almost always flood itself out instantly when you try to recrank it. We have to do a process everytime it dies. We unplug the battery. Then unplug the crankshaft sensor wire at the wire harness. Leave it unplugged a minute or so. Replug everything back up. And it will crank.

 

[ThatJeepingFamily]

And our jeep has a distributor and 1 coil pack. We have a 99 Jeep Cherokee classic 4.0l

 

[ThatJeepingFamily]

Checked all the grounds. Jeep still idled good. Drove it around in the driveway done fine. Drove it around the house (trail in the woods, little more room than just driving in the driveway). Going good. Let off the gas. And it died. So it will run when hitting the gas. But as soon as you let off the gas it will run rich and die. And flood out.

 

[ThatJeepingFamily]

We found the issue. It was the wiring harness rubbing the fuel rail. Melt the plastic protection and melted the wires. Got that fixed and she runs like a charm now.