I have a 96 XJ 198k 4.o auto. Last night when I was at work, i went out to go to dinner. It wouldn't start. no dome light even. got a boost, started ok. stalled then nothing again.
here's the mystery, went out at 8 pm it started no problem. it also started when i left at 1030 pm and again this am. Any ideas why it had no juice and then did without any charger or a boost? I'm baffled, there were no loose wires that I could find. I did nothing to it between 630 and 8, i wonder if the XJ-Fairy came and helped me out.

Thanks
Rich in Ct

 

whats the weather like there. wet/rainy? did the engine warm up or cool off in between those times? need some specifics for a better diagnosis.

 

Weather was dry, no rain. Parked it at 2 pm, went to dinner at 6. When boosted ran it for 15 minutes until 7 pm. Then it stalled and no power to dome light again. 8 pm just tried it for haha's and it started.

 

Start with the basics. Remove and clean battery cables. Use Dielectric grease when putting them back on the battery, then re-fresh all the grounds. Has to be something simple.

 

Also, check the connections on your starter.

Seems unrelated, but on mine, the connections got jostled when jumping/charging, which pointed me in the wrong direction for days until I figured it out.

Bottom line is that it costs nothing to check, right?