I have a 93 Cherokee xj. Just got it out of the shop. New starter new fuel pump and a few other little things. Runs great but just started having starting problems. It will start and then drive around. I’ll turn it off and it doesn’t want to start back up until after it’s cooled down. Someone said it could be the crankshaft position sensor? Any other ideas?

 

Can we get a little more info? When you say it doesn't want to start, will it crank and try to start, or do nothing at all? Will it ever not start on you after sitting overnight?

Just curious, what are the "few other little things"?

If you have never had the cps changed, that would probably a good place to start. But there are a few other things that it could be.

 

It normally starts just fine after sitting for a while. When it doesn’t start it doesn’t do anything at all like I have no power but all the lights come on and the radio works.

 

Have you checked to see if your reverse lights work? Next time it won't start, try jiggling the shifter while it is in park, or switch it to neural and try. You may have the neutral safety switch going bad. For it not to do anything when you turn the key, might not be the cps.

Google "Jeep cherokee xj neutral safety switch", you'll get plenty of results.

 

Thank you I will update this thread as I work on it

 

reverse lights do not work when it won’t start I tried jiggling the shifter and shifted to other gears and still won’t start. I will buy a nss and see if that fixes the issue. It’s old and has a lot of miles on it so I don’t mind throwing new parts at it. Even if it doesn’t need it it’s still good to have new parts right? Lol

 

Don't buy one just yet.

They go for quite a lot of money. Look up how to rebuild a NSS. It's easy and will usually require a little elbow grease and dielectric grease.

That was just a suggestion of something to check. I wouldn't want to see you throw money at it unnecessarily.

Do your reverse lights work normally?

 

thank you for the suggestion. I looked at it before I left for work it’s covered in old oil and dirt from a previous oil leak from the previous owner. I’ll try to rebuild it if it’s salvageable.
and yes the reverse lights work normally

 

If the reverse lights work on and off, it may not be a bad place to start. But I would look into the CPS as well. Don't buy a cheap parts store brand, look for a factory Mopar replacement.

 

I will definitely try and find original mopar parts. I don’t like cheap store brand parts. I will keep updating this thread

 

Before you buy any parts or change anything, go through and check every wiring harness connection that you can see or reach. By checking I mean uncouple, clean, dielectric grease, and reconnect.

Begin wherever the mechanics were and work your way out from there.

 

Gary,

If you get NOTHING when you're trying to start, as in no cranking of the starter, it's UNLIKELY to be a CPS issue. Typical CPS problems present as a "Crank-no-start".

Definitely pursue cleaning your NSS (I don't know much about that sort of thing since all my experience is with manual Jeeps), but you should definitely go through the wiring. I wouldn't be surprised if there's something loose with the wiring to the starter - clean and tighten the battery cables and the wiring to the starter.

Its actually a common issue with a simple loose battery cable where you'd get lights and radio, but nothing when you attempt to fire up the starter. It's because the lights and radio don't require a lot of energy to function, but turning over the engine with the starter requires a lot of energy.

Again, I wouldn't be surprised if the mechanics didn't make sure the negative battery cable was "clean and tight".

On my previous Jeep, an '00 Wrangler, my negative battery cable clamp wore out and was loose. I was super busy at the time and finding the time to take care of it was difficult for a couple months. For the most part, the Jeep ran fine, but from time to time I'd get in the Jeep and when I tried to start it I'd get nothing. The lights and radio would work fine. I'd jump out, fiddle with the negative cable (using the underhood light as a guide to see if it was connected) and then would get it to start. When I finally got around to fixing it, I bought a new negative cable that made a solid and tight connection and never had an issue again. That Jeep still has the original starter AFAIK 20 years and over 300k miles later.

 

I agree with Pat. It might be the CPS, or the CPS plus something else, but that's not the first place I'd be looking. Pat nailed it - check those cables. Positive AND negative. All of them.

 

If vehicle does not crank, that points to the NSS, rather than CPS, which would allow the vehicle to crank but not start

try moving the selector thru the gears repeatedly while you turn the key..if still nothing, probably worth checking if 12V is getting to the Starter Solenoid

It would be annoying to do the NSS only to find the Solenoid is failed

 

Thanks Mark!

O.P. Just so you know, I got a notification from the thread for Neal's (XJWonders) battery cable upgrade sets - he IS still taking orders for cables, but only for the next 10 days.

I absolutely recommend buying a set of battery cables from Neal/XJWonders. The cables are reasonably priced and he personally constructs them specifically for your year XJ with high quality components. His work is top notch and he stands behind them. If you're even considering replacing or upgrading your cables, I would contact Neal immediately and make sure you get a set while you still can.

I actually bought my cables last year as an xmas present to myself and they've served me well.