Hi All -

I have an 03 XJ8 w/ 84k. A couple of days ago, I dropped my wife off at the post office and left the car idling while she was inside (about 10 minutes and outside temp was about 50 degrees).

Realizing she was taking a while, I turned off the car and she comes out 10 seconds later, gets in the car and the car won't start.

The engine cranks, starts, but it putt putts, stumbles, the rpm's hardly get to 300-400 and then shuts off. I try a couple of more times and the same thing. I let the car sit 15 minutes and the same thing.

I have the car towed to my local mechanic and the next day the car starts right up and passed vacuum tests and threw no codes. He even tried to replicate the idling, etc and the car starts. I have the car back and has started every day since.

Any ideas what may be going on?

Thanks to all who answer.