CavalierLeif

Hi all,

I have a '98 XJ Sport 4.0L that was my daily driver throughout college. I retired it for about a year and a half, during which time it was sitting in a barn and driven very seldom around the farm. About half a year ago, while taking it down a muddy hill, the brakes failed and the front-end hit a fence. I replaced the radiator, A/C condenser, electric fan and since it was due for a tune-up I brought it to my mechanic to look over. It drove fine until it warmed up, at which point it would stall and die - particularly during deceleration and stops. When it reaches the temperature when it starts stalling, I also hear a slight clicking coming from in front of the drivers dash, from around the area of the power break booster - this only happens once the car is warmed up and driving, corresponding to the pressure on the gas.

Of course, when my mechanic looked at it/drove it, he didn't run into this problem since he didn't drive it very far - brakes were shot though, so he replaced those.


Knew I had a little work to do, so I started looking on forums - seems this problem isn't unheard of and there can be a number of solutions ranging from corroded grounds to bad fuel pumps to cracked exhaust manifolds. First, I put in a new batter after load-testing the old one, changed the oil and ran some SeaFoam through the vacuum hose to see if that would clear anything out - also cleaned the IAC and throttle body, put dielectric grease on the connectors, etc. Still didn't fix the problem. I installed a new TPS, spark plugs (Champion copper), wires, distributor cap - it idled a little smoother but still stalled out. The Jeep has no problem starting.

Most recently, I installed a new crankshaft sensor - hopeful that this would be the final solution. Man, was that thing a bear to get out/in, but with many socket extensions and some contortion I was able to do it. I noticed very little difference in performance - and the Jeep still stalls.

I'm running out of ideas here - I'd hate to keep throwing parts at it to no avail. Has anyone experienced this before and fixed it?

Many thanks,

Leif

97grand4.0

Parts cannon in full force here.
Ever hook up a scan tool and see what it says?

tjwalker

For the clicking you are hearing, best to get yourself a mechanics stethoscope and start poking around (carefully of course in the engine bay). There are so many possibilities and noises are difficult for us to help you with.

For the stalling at hot engine temp, is the check engine light on or have you seen it on? If so, retrieve codes for clues/guidance on direction to concentrate on.

In the absence of codes, a scan tool would be helpful. I would also consider testing the coolant temperature sensor (located on the thermostat housing). If that sensor goes south, the computer gets confused on whether it's a cold engine or a hot engine.

Also, be aware that the "ignition coil" can suffer from thermal (heat related) failure. That can also be tested with a meter and a manual, but be sure to test when the engine won't start or the test data may be within spec.

Good luck and keep us updated!

CavalierLeif

Thanks all,

The Check Engine light comes on when it stalls - I've hooked up a scan tool and got p0132, high voltage o2 sensor. I bought the sensors (NTK) and was able to install the rear - however, for the life of me I haven't been able to replace the forward sensor even with PB Blaster, warm exhaust.

Could a bad o2 sensor really be causing this?