Hey all, my mechanic and I have been after this problem for a bit. I have a 1992 xj Cherokee, inline 6. It runs pretty well, has about 217k miles on it. However, it cuts out occasionally. Sometimes at idle, sometimes when driving along at a steady speed. It's unpredictable and happens without warning. Everything suddenly goes dead. No hesitation, no sputtering. It will start right back up, immediately. If it cuts out while I'm moving along about 45 mph or so, it will often go off for about 2 seconds, then start itself back up and behave as if all is well.

It's gotten new plugs, wires, cap and rotor. Verified that the firing order is correct. Small amount of oil found in the distributor and wires soaked in it, hence the new cap and rotor. And the damaged wiring is replaced. Got a new idle control module. A little stumped here. Any suggestions? I will add that it has died at idle a few times in the 5 years I've had it, but this began happening a bunch this year.

 

crank sensor is failing is it occasionally hard to start

 

Never. Always starts right up.

 

Try a new crank sensor

 

Had that exact scenario with the Mustang some time ago. Would cut off randomly for a second while driving and catch itself and run like nothing happened. But if i was stopped, it needed the key. Fired right up everytime. For me it needed a new pickup in the distributor.

The crank sensor fails more then the pickup (also called a cam sensor or stator depending who you talk to). Newer XJ used a flat plate style. Pulls right off. The older needed the distributor taken apart. Dont know when they switched.

 

Thanks for the feedback, I appreciate it.

 

In addition to the crank sensor, check the wires that ground to the engine oil dip stick bracket. On my 1996 XJ (bought new) the grommet connections failed in about 2000. Replaced with a relatively cheap connector kit (generic). That stuff failed about 2011, and again in 2019ish. Used a short NAPA grounding strap from dip stick bracket grommet to reduce vibration on the ring connectors, then a heavier ring connector on each wire to the strap, bolted together with a bolt, nut, and toothed style lock washer, dielectric grease.

 

Well, my mechanic says that typically, if the crank position sensor fails, the engine would not immediately restart. But they're going to check the car's computer to see if there's any recent notification of it. So far, the computer keeps telling them that the jeep is running great. It's a difficult one to pin down due to its inconsistency. After they replaced the cap, rotor, and pick up coil, it drove great for 15 miles, then the next 15 miles, it cut out on me 2 times. Now it's been another couple hundred miles and no problems at all.

318SixPack, I will check the connections there, thanks.

 

The wires on our old Jeeps are getting really old, and really worn out.
Right now as I am replacing/ upgrading my engine compartment, I am finding a good portion of my wire harness has had MANY problems.
In fact one thing I just repaired is the wires going in to my TPS.
Here are a few pictures of the repair on just this ONE plug on the harness.


Exposed wires maybe touching each other?

First I pulled the insulation down to the connector, then clear heat shrink over the wire to the plug, then crimp connectors soldered.

Last step black heat shrink over the buttjoint.

 

Here are a few more. Under the convoluted tubing you sometimes find all kinds of things???

 

Oh man, what a nightmare to have to trace a bad wire through those harnesses. I might take it on if needed, but I fell about 4 stories earlier this year and I am still recovering, somewhat. So I cannot really do any of the work right now. I appreciate the input.

 

Chrysler used cheap wiring with stiff insulation. Thats why.