engine stalling and hesitating after warmed up.

How old are the plugs/wires/rotor/cap? How old is the coil?

A failing coil will cause all sorts of bucking and problems when it gets warm.

Go ahead and disconnect the TPS. The vehicle will run without it. See what that does. If the engine smooths out then it is either the TPS or the connection.

Check the engine ground strap and see if it has rotted. You can test for a faulty engine ground by putting a jumper between the engine and the frame or battery ground.

Last time I got that (last 5 miles home were at idle to maybe 1000 RPM max) I had the CPS lead shorted out against the exhaust where I forgot to tie it back). It would start and idle, but no way would the engine accelerate or run at higher RPMs. Talk about a "limp home" mode!

ok - coil, rotor, cap, wires all just replaced. Plugs are maybe a year old.

The engine runs no differently at idle with the TPS disconnected.

Yeah, I'm starting to suspect the CPS. I'm gonna try jumping the frame to the engine first, though.

It's getting worse - now it's pretty reluctant to idle. I can start it cold, it'll run for 10-12 minutes, and then suddenly die and be a real bear to get anything out of it.

no codes still.

Will H>

while none of the material I have for the jeep - including the service manual - have any reference to a "Top Dead Center" sensor - I think you're probably referring to the Crankshaft Position Sensor. They're the same thing, right?

I got one on the way, in the mail. I'll let you all know if it fixes it...

L.W.(Bill) Hughes III wrote:

Hi Elijah:

Wow - this sounds a lot like my post... See my recent post: "Help with 1989 Cherokee XJ LTD rough idle and acceleration"

My problem also started after the truck sat outside for about a month without running.

I'm still trying to solve my problem.

Although a TPS can fail only at some rotations, it can fail altogether too. It sure is easy to change them, and they don't cost much. I've had two go bad on me - one on a 97 TJ in less than 3 years service, and one on a 2000 JGC in less that 6 years service.

You can also use a common ohm meter to test the TPS, but it can be hard to find bad spots this way.

Paul Nelson

in article S6mbh.3053$ snipped-for-privacy@newsfe23.lga, NT at snipped-for-privacy@hotmail.com wrote on 11/29/06 2:31 PM:

HI folks - I got my truck working good. It ended up to seemingly be just a bad battery connection! I accidentally discharged my battery (leaving the truck on after a troubleshooting session) and when I attached my charger to the battery terminals, the charger registered no battery. Curious, I pulled the terminals and attached the charger directly. This worked, and charged the battery, and made me suspicious. So I took one of those little wire-brush battery terminals to the battery and lo, the car started and ran and hasn't had any problems since (except the new "too cool" code I'm getting, *sigh*).

I felt kind of stupid, after all that, it was just the battery. it didn't look corroded at *all* and I had pulled and replaced the terminals already. it needed to be brushed.

I had ordered the CPS already, and so I put it in last night anyway (the old one had tested bad with the ohmmeter). I found it a real bitch to get at - finally came at it from below and behind with two long ratchet extensions on my handle, and my other hand coming up in front of the bellhousing to help position the socket. Once the two bolt were broken free it was pretty easy, though.

next: new springs all around, complete new front breaks, new thermostat & coolant sensor.

thanks, everyone!

NT wrote:

Thanks for the follow up. It's nice to know the outcomes. Jeeps are really picky about battery power. Our Cherokee can have enough power to turn the starter but not enough to fire the spark off at the same time if the battery is too low or has a poor connection.

Mike

Simple solutions to complex problems are the toughest to find. Pat yourself on the back for sticking with it long enough to find the gremlin. Thanks for letting us know what the problem was.