indyhoya

Couple weeks had trouble starting my 1996 Cherokee. Would crank but not start. Was able to jump it, though after driving a little more than a couple hundred yards it puttered out. Jumped it again but was having to consistently give it gas to keep the engine running; anything below 2000rpm it would start to sputter and eventually did conk out when shifted into drive.

Didn't drive it for a couple weeks as I don't use it as a daily driver/was out of town, and then took a look at a few things this weekend. At first try, it started up right away no problems. Battery reading was right at 14V, also checked the fuel rail and was getting gas no problem. Let it idle for a while then drove around the block for about 10min at various speeds-didn't have any problems at all, ran smooth the whole time.

Replaced all of the spark plugs and cleaned the wires about 3 months ago, my dad's suggestion was to replace the distributor cap & rotor and replace the wires as a first try. Any other ideas on what could be causing intermittent starting problems? Thanks in advance

NewJerseyXJ609

Crank positioning sensor would be my guess!

They go bad all the time and give the same results that your getting. It wouldn't be a bad idea to check the cap for cracks and your rotor for wear.

indyhoya

Thanks for the tip on the crank positioning sensor.The rotor was pretty worn so replaced that and the distributor cap today. Did a good amount of driving today to get the parts and run a few other errands, no problems starting at all probably half a dozen times or so. Does the crank positioning sensor tend to malfunction only once in a while when it's going bad?

NewJerseyXJ609

Yes.. If i were you I would definitely replace it. The cps went out in my 96 exactly how your explaining.

And it went out on my 95/93/94....lol not my 00 yet! Knock on wood!!

kennzz05

is it the cps that everyone says to get the mopar part as aftermarket have issues?

indyhoya

Good to know-thanks! Interested as well in what cps you recommend?

Update: Doesn't appear to be a sparking issue as I still have the problem after replacing the distributor cap, rotor, and wires. Have had no problems starting it but on Sunday night after driving for about 10 minutes had it cut out on a side street at a low speed and another time coming home at a stop light. That being said, at other times it will idle just fine, up to 10-15 minutes in stopped traffic as well. After it cuts out it is hard to start back up, generally have to give it a good amount of gas as it cranks.

Twice now when it's cut out it was after giving it a small amount of gas (say when slightly accelerating out of a turn on a side street). Both those times had the odd sensation that the jeep accelerated moreso than it should have given the amount of gas it was given and that it was sort of gliding along at that low speed and then will cut out.

Check engine light has never come on but tried doing the key trick to get some of the codes; came back with both 12 and 17. I've read 12 is the start of codes and in other place seen in corresponding with a disconnected battery sometime in the last 50 key strokes. It seems 17 corresponds with a low engine temp.

Any additional ideas out there besides a bad cps? Thanks in advance!

NewJerseyXJ609

It's most definitely your cps. Change it and avoid all the headache. Just make sure to buy a quality replacement.

Just because you replaced your rotor and cap doesn't mean you have spark. Have you tested for it? A bad cps will cause no spark/random shutdowns.. Etc

Very common issues for these vehicles. I've seen people chase random shutdowns and no starts all over. Replacing every part on the jeep. And the whole time it was just the cps. It's a pain in the butt to change for the first time. You'll need some extensions and a wobble.

NewJerseyXJ609

Also just so you know a bad cps doesn't always give you a check engine light. I've seen them be bad many times with no cel and no warning. Some just crap right out and some will slowly die.. My 96 would start and die a couple times. Then I would get a mile or two down the road and would shut off and not start. I changed a ton of parts on it because I didn't think it could be the cps since there was no cel. I must have changed every sensor down to the pcm. All along it was the cps.

indyhoya

Alrighty I'll do the cps before anything else. thanks for pushing me in that direction. Having replaced a number of these guys-any suggestion on who make's the best replacement?

NewJerseyXJ609

I'm going to be honest here. I've done at least 5 cps' and I've always just gone down to auto zone and picked one up.

Alot of guys will steer you away from that and say head to chrysler for a Mopar replacment. I know they are 80 bucks at auto zone.

Like I said before your going to need a 3/8 wratchet, extensions and a wobble. I'm pretty sure the 2 bolts are 12 or 10mm. It's on the passenger side top of the bellhousing. Your best bet is to get it from underneath. But I've been able to get one from the top. It just takes patients because it's in a bad spot. Make sure not to drop the bolts down into the bellhousing!

I'm confident that this will correct your issue.

indyhoya

Update: I finally got around to replacing the cps today. Started up no problem, drove it around for about a half hour, no issues to report. Took a short trip tonight and on the trip home had a bit of a hard start where it was cranking but had to give it gas to get it going. Drove home no issues. At home started it up about two dozen times and only once or twice did it not start up right away and needed a little bit of gas to turn over.

I'm worried that I may not have fixed the real problem and that there's still the possibility of conking out somewhere. Any ideas?

NewJerseyXJ609

Hmm, do you know when the last time the throttle body has been cleaned on your jeep?

If not it's really simple. Take the intake tubing off of the throttle body and undo your throttle/kickdown/cruise cables. Then unplug the tps iac and may sensors. Then your going to need a wratchet with an extension/10mm socket. Take out the four bolts and pull the TB out. Give it a good cleaning with some parts cleaner. You may or may not be able to salvage the paper gasket inbetween the TB and the intake manifold.

Also, last time you changed the fuel filter? A bad tps can also cause this issue. But let's get some facts straight and do some testing before we go buy more parts.

Sorry the cps didn't fully fix the issue. But it is honestly never a bad idea to throw a new cps in. One less headache down the road.

indyhoya

Thanks a lot for the quick feedback. I bought the XJ last June and honestly don't know when/if that work was done. It's only had one previous owner-I've reached out to him to see if he knows.

Cleaning the throttle body regardless seems like a good idea that I'll try to find some time to do this week. I'll let you know what I hear back on the fuel filter/tps.

Thanks again!

indyhoya

Was out of town for a couple weekends and then really busy for most of april so far, but wanted to post an update.

Looks like the cps may have been the main issue after all I did quite a bit of driving last weekend without having done any other work and had no problems. This weekend cleaned the throttle body and the iac-the iac was really gunked up. still no problems to report.

Previous owner had never cleaned the throttle body, or didn't have any knowledge of the tps or fuel filter having been replaced. i know I've been running ok now, but is it worth replacing the fuel filter at lest?