88 XJ shutting off while driving

Hey fellow jeepers,

I've had my 88 xj pioneer for some time now and when I got it, it had an issue where it would simply shut off of the weather conditions were bad in the New England area, but I resolved that. Now, when i am able to get it to start, it seems to just shut off randomly as if someone just removed the key while I'm driving, no matter if traffic, highway, city, ect.. I have replaced everything I can think of, (CPS, TPS, ICM, ign. Coil,) but I can't seem to figure it out. Original 1988 Renix motor, 114k miles

Any advice or knowledge is appreciated. #jeepdown

Sounds like you may have high resistance wiring between the CPS and the ECU. May be something as simple as oil in the CPS connector.

You need fuel, air and spark. Try to figure out which one is missing when it craps out on you.

If it happens when you take your foot off the gas it could be sticky IAC. If the iAC sticks shut it will choke the engine (no air). Pretty much the same thing happens if the EGR sticks open, though it may not stall and just idle really poorly.

If your ballast resistor is acting up it may mess with the fuel pump voltage and cause issues. Jump the ballast resistor and see if it helps any.

If the CPS (or wiring) is messing up you get no spark and no fuel while cranking. The exception to the fuel thing is you will get a 2-3 second prime when you turn the key from off to run.

Not everything that can go wrong, but some of the more common ones.

Cruisers checklist is always a good bet if you get into one of those situations where swapping out parts doesn't seem to help.

Don't overlook the obvious, I've found an amazing amount of garbage in fuel filters over the years. Have some spare fuel line handy, as the old stuff tends to disintegrate, some extra hose clamps handy and dump the contents of the fuel filter into a clean jar, blow on the outlet end. Depending on how much junk comes out, you may need a new fuel filter. The fuel may tend to siphon from the tank when you remove the filter, a good idea to have something handy to deal with this, like a short piece of fuel line with a plug in the end.

Click on the link below. Do posts 1 through 5, and maybe even 27.

https://docs.google.com/file/d/0Bz4d205LaED2SUxMOGZnY3RjaEE/edit?pli=1