Had a new developement this morning. As I was getting ready to leave for work, the old girl wouldn't start.
Battery is good, heard the fuel pump come one but, it won't turn over.......not even a click and it was doing fine yesterday.
I'm guessing maybe the starter but, I didn't have time to troubleshoot this morning. Any ideas?

 

automatic try moving shifter back and forth see what happens ,also tap starter with hammer see what happens

 

Try to start it in neutral.

 

If the accessory and ignition position turn on fine and it wont just physically start cranking it could be that there's an issue with your starter relay.

 

I had the rod from the lock cylinder to the ignition switch on the firewall break on me before.......sounds similar. All else fails check that.

 

Well it's official..........my XJ is posessed!
I got all sorts of ideas of things to test and how to; from my fellow mechanics at work such as: battery cable connections, ignition fuse, relay, switch, starter solenoid and the starter itself.

When I got home from work, before I started testing things, I decided to try to start it just for fun. She cranked right up like normal! WTF? I shut it off and started it 4 more times.........perfect every time.

I still have no idea why it wouldn't start this morning.

 

If you hold the key over, and jiggle the shifter in park or neutral and it starts, it's your NSS. http://bc4x4.com/tech/2010/jeep-neut...ty-switch-nss/


Mine has had issues for years. Just got a little worse. When it's not hot, and not cold I need to pull it back from park "just so". Warm it goes, and when I park it warm it starts in the AM. If I "re park" or something I need to do the jiggling and fiddling.

 

You can use screwdriver to connect small and big bolts on starter solenoid, just don't touch starter.

 

IMO
NSS dirty or Starter is going out.

My jeep is plagued with both haha same symptoms for both issues. excepts I can play with shifter or put in Neutral and it will crank its the NSS.
Tap the starter with a hammer and it will crank for the starter issue. I will be replacing my starter before our next ride so wont have that one anymore.

 

Its probably what Dflint is saying. Mine does this too and I have to wiggle it to start.

 

It did it again this morning so, I popped the hood and checked the battery terminals. Although the clamps were tight on the battery, the cables had some movement where they attach to the clamps. I had this problem once before and was able to fix it by flattening the bar and tightening it back down.
I'm just going to go buy some new ones, clean up the cable ends (the exposed wires), tighten everything down, then spray on some protective coating.

 

Check the posts above regarding your NSS. Write-up about cleaning it available in forum.
Yes, it could be other things, this is however likely on top of the list (and can be ticked off from the things-to-do list otherwise

 

A multimeter is your friend. When this problem arises again get a helper and do this test: Set meter for DC volts to read 12 volts. The usual setting is 20 Volts. Take a reading of battery voltage. Connect meter to small wire on starter solenoid. Have helper turn key to start. Each time the key is held to start, the volt meter should read battery voltage.

Remain clear of moving parts in case engine turns over.

If you get a battery voltage reading the starting circuit is good. Wiring, ignition switch, relay and NSS. If you get no reading or low reading then you have to check these parts. Start with the NSS as it is the problem child.

If you get a battery voltage reading then check the battery, cables, terminal connnections, (at battery,ground and starter), and the starter/solenoid itself. At this point using the hammer technique may be useful, just dont go overboard with it. What this does is shake the interior parts of the starter and maybe fix a poor internal connection or corrosion problem.

It could also be worn solenoid contacts. Cheap and easy repair.

 

YOuR Neutral Safety SWITCH is bad!!!!

PUt the JEEp in Neutral then start it!

!!!

 

It's not that. I've already tried that as well as jiggling the ignition switch while turning it to start. No results on either.

Moving the battery cables around however, does yield results. The terminals are free of corrosion, I used a wire brush to clean the exposed wires at the end of each cable, installed the new cable ends and sprayed on the protectant. So far................no problems.