99 XJ sport, This is happened a few times recently, it will hesitate to start when turning over, but it always turns over. Today, it refuses to start and the negative battery terminal was hot enough to burn my finger. Granted I was trying to make it turn over for about a minute collectively, So was it the extended attempted start of time that made it overheat or something else? I know I need to load test my battery, alternator and starter to see if they are producing accurate numbers, but it's a damp day and it seems to happen when it's damp.. Grounds and leads are tight and clean. Runs well and starts usually. There's a slight whine when it's cold, like I said, I gotta check the alt. for sure.. Thoughts?

 

Check for spark? CPS is a common issue for no spark no start. Terminal proly got hot if you let it turn over longer than a few seconds and kept going. When I done my engine swap. I had no start at first and would keep going. the terminal would get hot and lead me down another road. I ended up changing all the grounds until I finally checked for spark. My issue was the CPS.

 

Concerning not starting: Your PCM requires a minimum of 9 volts to operate properly (if at all) so perhaps your bus voltage is dropping below the 9 volts when cranking, which could be attributable to a defective battery, or ground circuits. How old is your battery? Generally a battery is good for five years.

A bench check of the battery is certainly in order.

When the engine is running, what voltages do you see on your voltmeter? Does it look like your alternator is charging normally or does the charging voltage stay above 14 volts continuously. If so, the battery is struggling. If the voltage stays at 12 volts initially, and thereafter, the alternator is struggling.

And, you're right, a check of your alternator is required. Especially if you hear it whining.

Concerning the starter: The starter is grounded internally to the engine through the torque converter cover (spacer) between the bellhousing and the engine. When I did my RMS I removed the starter and found the surfaces between the starter and the TC cover were badley corroded. I didn't have starter problems but obviously I cleaned up these surfaces before reassembly. You may want to check this out on your XJ.

 

Good call. I suppose with a good scan tool I can look at voltage to CPS. This should tell me if its good right? Or is there another way? Thanks man!

 

Battery is new, but.. The day I got it installed, I left the headlights on for about two or three hours. It started up fine, but I'm wondering if that didn't cause an issue somewhere.. I'm pretty sure battery's ok, but the alt. seems to be a likely culprit.. I will have to double check the voltage at start up, to ensure 9v minimum. As it sits now, I get a steady 14-14.4v when running, according to dummy gauge, so again, this'll be something I will check with a good multi meter. As for comment regarding the starters ground point, that'll be something I might just have to check into later this spring when the weathers a little better.. Assuming I get this resolved..
Cool thing is there's a local family that does electronics around here that rebuilds alternators fairly cheaply.
As for the rest of today, it started just fine. I still wonder if it's not something moisture related? Idk.. A multi meter will tell me a lot. Thanks or the info man!