PAIXAO

I was on my way home from work yesterday evening travelling about 60mph when my XJ surged for a bit then shut down on me. It will start right up then die immediately. If I floor the pedal while starting it will fire up but if I let the RPM drop below 3000 it dies again.

Based on my searches here I have narrowed it down to a few parts that could be faulty. The TPS and CPS I have ordered from Jeep. I am wondering which MAP and IAC sensors everyone is using. Jeep has informed me that the OEM MAP has been discontinued.

This XJ is new to me so I don't mind replacing these parts for peace of mind.

Your input is greatly appreciated.

DFlintstone

I can't guarantee for certain, but over allot of years it seems to me Napa holds the bar up a little than some. My .02 anyway.

You might try the "Key Trick" (OBD is On Board Diagnostics).

OBD1 Models: 1991-1995
1) Start engine (if possible). Move transmission shift lever
through all positions, ending in Park. Turn A/C switch on and then off
(if equipped).
2) Turn engine off. Without starting engine again, turn
ignition on, off, on, off and on within 5 seconds. Record 2-digit
fault codes as displayed by flashing MIL.
3) For example, fault code 23 is displayed as flash, flash,
4-second pause, flash, flash, flash. After a slightly longer pause,
other codes stored are displayed in numerical order. When MIL begins
to flash fault codes, it cannot be stopped. Start over if count is
lost. Code 55 indicates end of fault code display.

PAIXAO

Ran the on board diagnostics with the key while I was waiting for the tow. 55 was all that was displayed.

Went ahead and ordered the TPS, CPS, IAC and MAP sensors. Went MoPar with the brand on all if them. It was tough to source them all, but finally found a place online that had all of them. $302 later and all I am waiting for now is for them to arrive.

DFlintstone

The CPS on my 90 has 7/16, (11mm) hex bolts. Here is how you go at that. You lay with your feet out under the passenger side. You can reach past the front drive-line to hold it with your left hand. If your forearm is larger than a quart mason jar, pull the front drive-line. Really, you need your left hand there.

7/16, 11mm., to > 3 inch extension > universal > to 18-24 inches of extention to put your RIGHT hand on the 3/8 ratchet drive down near the trany cross member. With your left you WILL NOT drop a bolt in there. (be cautious as you take them out)

Before you start, tie a long (5 foot) string to the old CPS wire/plug. You can then use that to haul the new up. Just cut the wires of the old if they go through a ridiculous ring off an engine to tranny bolt. S-can any plastic shield that might be there. Zip tie/ make sure your new wires are not chafing on an edge or on something hot.

I'm sure that applies to 87 to 90. Not sure what bolts, (fasteners) you might have.

cruiser54

This will help you get oriented. Be sure to rute the wires properly or they will get melted on the exhaust manifold.

PAIXAO

Excellent! Thanks for all your help.