dt750

I just hooked up a remote start to my 1998 xj and it turns over but no start. so i unhooked the remote starter. but same thing no start. gas gauge isn't working and no spark? any ideas were to start? Edit: if i unhook the battery the gas gauge will work briefly and then drop back no empty. all fuses look good both under the hood and in the cab. thanks dt

dt750

edit: fuel pump kicks on. i took the plastic covers off the wiring harness and no burned wires or shorts. I'm leaning towards it being the ECU. will an ECU from a 1996 work? both are 4.0 auto?

BlueRidgeMark

Chances of it being the ECU are very small. Just because you don't understand it doesn't mean it's the ECU.

First, verify if you have fuel (at the correct pressure) and spark.

dt750

getting fuel, i'll check pressure tomarro, but no spark at all

Mjrpayne

By chance is the hood open? Could it be the safety switch for the remote starter?

dt750

unhooked the electric starter. still the same

BlueRidgeMark

Fuel is nice, but what about fuel pressure?

But since you have no spark, that's the place to look first. Without trying I can think of three likely candidates other than the ECU:

1. Crank Position Sensor (CPS or sometimes written as CkPS)
2. Cam Position Sensor (CPS or sometimes written as CmPS)
3. Automatic Shut Down relay (ASD)

The easiest of these to test is the ASD. It's the same relay as the others in the PDC. Just swap with one of the other relays and see if it starts. Quick and easy.

If that doesn't help, search on testing the CPS (both of them), There are many threads on it around here, and some good videos on YouTube.

If it IS one of the sensors, make sure you don't buy any aftermarket replacement. The track record on them is very bad, ranging from bad out of the box to only lasting a year or so (if you are lucky). Get NGK/NTK only.

OutbackOz

if the crank sensor is kaput it wont go but wont affect the fuel gauge check your grounds on the block at the base of the oil dipstick

dt750

thanks, I'll give them and the cps's a check when the sun comes up. and thanks to all who have taken the time to respond, sure do appreciate them.

Noah911

Bad crank sensors have been known to effect the fuel gauge. They share the same circuit thru the ASD relay. This issue has also been reported as happening to other Jeep owners in the past when they were having issues that were directly related to having a bad CkPS sensor.

dt750

the previous owner just replace the ckps, but if I screwed something up hooking up the remote starter maybe I cooked it. or i've seen new ones go bad. Thanks for the info, I never new the ckps could affect the fuel gauge. good info to know. thanks again..hope I can get it fixed...hunting season starts saturday...lol

Noah911

What brand of CkPS is in there though? Non-Mopar? Plus, CkPS is one of the primary suspects when you have no sparks...

Noah911

Having had a previous owner replace anything also makes whatever that was another highly likely suspect!

dt750

Definitely gonna check it. i agree it's one of the most likely culprits. I hope I didn't come off as arrogant, by saying it was replaced. just trying to make sure ya have all the info on what's happening.

the previous owner bought it was going to use it to drive around his coyote dogs around, he drove to a garage (he doesn't work on vehicles at all) to have the ckps replaced. drove it home, blew a brake line and parked it. he realized having 3 coyote dogs in the back of a jeep was gonna be really stinky, so he went and bought a new truck and cages for in the bed. jeep sat since January until I found it, fixed the floor, rocker panel, break line put a battery in and everything has been great..til I decided to put the remote starter in. also the neutral safety switch doesn't work, the relay is just grounded to the battery, not probly related to the issue at hand, but as a member of a tractor forum I know how frustrating it is to try and answer a question with no information.

dt750

if I did the test right the crank sensor is good, but i have no power to the sensor. I had the boy turn over the jeep and none of the wires on the crank sensor lit up my test light. after I warm up a bit I'm gonna test the cam sensor. when getting in the jeep i noticed this wiring. I've seen several in the wiring harness and they have all had another wire coming out of the end of it? any idea's?