'99 XJ starting problems

[Bzamora]

On my '99 XJ, 177K with the 4.0 and auto trans I've got an intermittent starting problem. When it's warm (such as after a long drive and stopping by the grocery store on the way home), when I get back in it and turn the key the engine will barely turn over. Let off on the key, try again and it starts fine. It has been doing this with increasing frequency. What should I suspect first... battery, starter, relay?

TIA

 

[sidewaysstarion]

Battery or battery cables, how corroded are the battery connections?

 

[Bzamora]

I always keep the terminals clean, however this vehicle has gone through a fair number of batteries over the years because it's only driven about once every couple of weeks. So it sounds to you you more like a connection problem? I'll probably stop by the local Lester Schwab today just to see if they can do a load test on my battery.

 

[fsupaintball]

Sounds like it could be your Neutral Safety Switch. It's attached to your transmission and if it doesn't think you're in park, it won't want to start. Typical symptoms include reverse lights not working properly, occasional random startup trouble. Sometimes you can wiggle the shifter and try again, sometimes shifting a bunch then putting in park and trying again can make your engine turn over, and sometimes just waiting a few minutes works.

Regardless, if you're having these issues with the NSS, it'll need to be fixed or replaced. It's kinda spendy so I'd recommend googling "clean (or adjust) neutral safety switch"

 

[birchlakeXJ]

Clean and inspect every inch of battery cables. Load test battery. Never hurts to refresh all engine grounds.

If the engine even tries to turn over, the problem is not the NSS. If the NSS is on the fritz, it will completely inhibit power from getting to the starter.

 

[Bzamora]

The engine will try to crank, but then complains like it's a bad battery or starter solendoid. But then as soon as you let off on the key and try again it cranks and fires up normally. What annoys me is the fact that it's so intermittent. But I don't think its the NSS.

 

[westvirginia24976]

I'm not familiar with the starter circuit, but it sounds like some type of relay may not be making connection well. When you de-energize the control circuit and re-energize you are essentially re-positioning the mechanism responsible for making the contact for the load and it makes a better contact the second time.

 

[fsupaintball]

The engine will try to crank, but then complains like it's a bad battery or starter solendoid. But then as soon as you let off on the key and try again it cranks and fires up normally. What annoys me is the fact that it's so intermittent. But I don't think its the NSS.

If it tries to crank, agreed.

I'd check the wires from the battery all the way to the starter.

 

[sidewaysstarion]

It could also be a failing starter solenoid.

 

[Bzamora]

Well, I'm first trying a new starter relay after I finish checking all of the connections. It's a $12 part so what the hey. I drove around hitting stores during my lunch break and had no problems starting, so the intermittent nature of the problem is going to make it hard to solve. Knowing my luck it'll finally crap out completely when I'm right in the middle of a gangland intersection at 3am.