Jag XJ8 starts but then dies right away.

[Paul Romans]

Might be the wrong forum for this, but looking for help. 2004 Jag XJ8, 121,000 miles, Had it 2 years, no problems, but died on the road yesterday. Cranks and starts great, revs to about 1000 rpm, but then cuts off right away, within 1-2 seconds. No misfire, no rough running, it's like the key was turned on then off again.

Fuel pump problem was suggested. I'm pretty sure I can hear the pump humming in the back when I turn the key, will check more thoroughly today. Any ideas? Thanks.

 

[mezy]

Could be debrie in the tank, had a car years ago that would do the same thing, would die then when left for a few minutes would start then die again, turned out the pick up pipe filter was clogged with chit, pulled the tank and found the coating from inside the tank had started peeling off
looked like the tank was full of wet leaves.

 

[Paul Romans]

Thanks, had a similar problem once with a Ford Explorer. The tank was full of silt because the fuel filler pipe had a hole rusted in the top and the rear tire always threw dirt up onto it where you couldn't see it. Took a looong time and 3 fuel pumps to figure that one out.

Anyways, someone on another forum asked if the Jag would keep running if the accelerator was depressed. Tried it, no change at first but after a few attempts if did keep running, albeit very rough. Continued manipulation of the pedal gradually improved the situation, and now it is running normally. I've started it a dozen times, everything works fine. I haven't driven it anywhere yet, don't trust it.

Thanks again Mezy.

 

[LarryK]

Need to scan and check fuel pressure and maybe clean throttle body and check the tps. Check grounds to coils. You may have two fuel pumps, high pressure and low pressure so pressure and volume check. Check vent on fuel fill cap and tube. Could be as easy as new fuel filter.

 

[equiprx]

First thing to do would be to check the condition of the fuel filter.
Dump the contents into a clean container and see what drops out.
Change the filter anyway unless the PO can assure you it's new.
Run the car briefly without the filter connected and see what comes out.
Have you checked to see if there are any codes coming up?