My 2001 XK8 has been idle for two weeks while I replaced the secondary tensioners, replaced the spark plugs, and gutted the interior to replace the two hydraulic hoses from the trunk to the roof latch cylinder. After getting everything back together, the engine would crank fine but would not start. The plugs have spark and I can get the engine to run briefly using some starter fluid shot into the intake. I hooked a pressure gauge to the fuel rail valve and get 0 psi when cranking. No fuel bleeds from the rail valve either. I have checked all fuses, swapped the fuel pump relay, reset the inertia cutoff switch and can't find anything out of order. The hydraulic pump power lead was disconnected and the pump removed from the mounting location (all hoses still attached) to drain the old fluid, but again, nothing in the trunk appears to be amiss. I removed the back seats, driver seat, console, and various panels to pull new hydraulic hoses. Does anyone have any suggestions as to what I may have missed or how I can further troubleshoot the mystery? It would seem unlikely the fuel pump has ceased to function sitting idle for two weeks, although I have read some accounts of having a fuel pump die after prolonged storage. This is very frustrating to try and upgrade a vehicle's condition and cause something else to fail that appears unrelated. Any advice will be greatly appreciated and possibly keep me from wasting perfectly good weekends chasing gremlins.

 

You have checked the relay and fuse for the fuel pump already. The only other thing that is worth checking is OBDII codes. If there are no obvious system faults indicated over OBDII, then the fuel pump is definitely the most likely suspect. It is not uncommon for them to fail in the mode that yours may have.

 

The pump is 13 or 14 years old (if original??).
The replacement interval seems to be around 100k miles so it might be time??

I just replaced a customer 2000MY XK8 fuel pump at 99000 miles as a preventive measure. He did NOT want to get stranded like many do at this mileage.

My 1999MY XJ8 fuel pump went at 102000 miles and I have 103000 on my 2001MY XJ8 so it will get replaced SOON!!!!!!!!!!!!!!!

Change the fuel filter when the pump is replaced!!!!!!!!!!!

bob gauff

 

See if this helps. Also do not spray starter fluid into the intake you stand a chance of cracking the intake manifold.

Link to Fuel Pump Electrical JagRepair.com - Jaguar Repair Information Resource

 

Have you measured voltage from the pump relay? If that's ok, then try start with another key.

 

Thanks. Gus (see other responses) provided me with a good troubleshooting guide to check what you recommended. I sincerely appreciate all the responses and will reply with what I find. I now have a direction to pursue.

 

Thank you for the troubleshooting guide and electrical diagrams. This is great and I will begin the checks this evening.

 

I am the second owner and the pump is probably the original one. The car has 44K miles, but I agree the age is a significant factor. I have some electrical troubleshooting recommended by the other replies to complete first before pronouncing the pump dead. Thanks for sharing your experience.

 

Good luck and keep us posted. I must admit that there are two nasty repairs that I dread when the time eventually comes - the fuel pump and the green shower. My wife's 2006 XK8 just turned 80,000 miles during the July 4th weekend so I continue to keep my fingers crossed and perform my weekly ritual spirit dances around her XK8....

 

I used the troubleshooting guide from jagrepair.com sent to me by Gus. I checked the 5 and 20 amp fuses with an continuity tester and found no issues. I removed the fuel pump relay and tested the voltages with the ignition key in the II position. Everything tested fine (although the jagrepair.com guide may have a typo and reversed the voltages for Positions 1 and 2). The last check was to connect the fuel pump directly to a 12V source at the removed relay location. Nothing, no pump spin-up, just silence. The jumper didn't even spark. Note: The 2001 hot wire for the fuel pump is brown-white, not brown-yellow as the 1999 model has. I disconnected the wiring harness from the fuel pump and connected this section to the 12V source, including ground wire, and still nothing. The fuel pump motor must have an open in the circuit. Unless anyone has any follow-up suggestions, I am declaring the fuel pump deceased and will start ordering parts for another weekend adventure. I have experienced the green shower and a fuel pump replacement in one month. However, the XK8 is still one of the coolest cars on the road, when it runs.

 

My 2001 XK8 was returned to service last Saturday. A new fuel pump with filter was installed with no surprises. I modified the front left corner of the fuel tank and removed the excess metal to allow the tank an additional 1/2 inch of clearance between the tight trunk walls. The fuel lines were the greatest challenge, but persistence and some ingenuity with long tools will get these out and in. The foam material underneath the tank on the trunk shelf has a tendency to slide forward with the tank installation and will cover the fuel line opening above the differential. The old fuel pump was the original manufactured in December 2000. This is a good data point for the length of service life for other owners that have pumps greater than 10 years old.