went to the store and poof! Car in limp mode then NOTHING! Towed it home then started to troubleshoot. First off tried a little starter fluid.,Started right up.then checked fuel pump. I hear it buzzing on start up but it almost instantly stops. I thought maybe the Fuel driver module. I purchased a new FDM and installed thinking everything would be fine. Uh, NO! Still no fuel pressure. Battery is new, has 12.80 volts sitting. hot wired fuel pump car starts right up. Next day i decide to install a new fuel pump. Being a fixer and not a replacer, i spend hours looking for a suitable fuel pump motor only! I did find one and will post the Part number in a separate post. Thankstothe O Reillys parts guy who helped cross reference with Catalog Books! Jeesh those things are full of info you dont see online anymore. Well back to the 2004 XK8 installed new fuel pump and found a bad connection inside the tank on the + side connection.Cool, my problem is solved! NOT! I cant seem to find this problems root! could it be the crank or the cam positioning sensor not telling the ecu to send power to the FDM?

 

The very LAST thing I would use on a modern Jaguar is starter fluid. The very FIRST thing would be my scantool.

Graham

 

Ok- first, breathe a little then lay out the symptoms here- I would bet that you will find the solution in an existing thread.

1. You said limp home mode then you had it towed. Did it start, but wouldn't drive? What EXACTLY happened?
2. Why did you replace the fuel pump when it worked hotwired? I guess good job since you found a problem....
3. You can't spray fluid into the throttle body because you are bypassing the MAF which is integral to running.
4. It sounds like you have pressure until it starts up- does the pressure go to ZERO or just low then? This is a very important piece of information.
5. Run the scanner and come back with the codes as Graham mentioned, it may give us some clues and point to the issue.

 

Lived in costa mesa years ago. Worked at Gary Grays Jeep for years!! Ok car was running fine. Went to the store and it started to stumble then it got worse. giving it pedal would kill it. just letting it run on its own would get movement at about 4 mph. Restricted performance light came on,so i decided to tow it home instead of chancing it about 1 mile. after it got towed i checked fuel pump and heard nothing on key turn. Fuel rail also had no pressure. So the next thing i did was find a fuel pump motor to install. (no small task just finding one.) Finally did find and upon r&r found a loose connection on + terminal of pump motor. Thinking i was a GENIUS i put back together and had no start,cranks fine but no detonation. Tried some MAP cleaning and found the car will start with residue map cleaner vapor. Not starting fluid! I went to get a scanner and pulled these codes. p0453,p1236,p1638

 

rail seems to have no pressure until i hotwired new pump. then car starts right up. i replaced fuel driver module thinking it was bad. It wasnt. so i gots a spare.

 

I know that the fuel pump will stop if you are at full throttle while cranking. Best to get everything at baseline before going further- check intake snorkel is in place and there are no leaks, clear all the codes and do a hard reset on the battery.

 

One other quick thing- remove the battery cables and clean both. I know sounds rudimentary, but one of your codes is a weird one- P1638 and points to the ECM which I am NOT inclined to think is the issue at this point. I have an XJ8 with an intermittent no start click anything issue until I cleaned the negative cable where it goes to the chassis BAM no problems after that.

The other possibility is wiring at or around the tank area- look for things either unplugged or maybe grounding? Fuel tank pressure sensor is one of them. (P0543)

 

Car runs fine. Check voltage at connector after Fuel Driver Module its 11.3 continuously. check continuity thru same connector to pump and its fine 1.4 on new pump and good old pump. so what is holding voltage back to pump?

 

Recently on my 2000 xk8 I had similar problems.
No fuel at the rail.
I couldn't hear the fuel pump operating.
Fuse and relay were ok
I replaced the fuel pump.
Fuel pump still wouldn't work.
Bench tested the old fuel pump and it worked.
Checked power at the connection from tank harness to where it plugs in at the right side of the trunk( boot). I had 12+ volts at the chassis harness.
I replaced the harness with one from one of my parts cars. Still the pump would not operate.

Turned out to be the hot pin for the fuel pump was not making a good connection. I bent it to where it made a better connection and all is good now.
Don't know if this is your problem but it doesn't hurt to check.

 

On the '97 there are a couple of ground wires attached to the trunk wall. Can't speak to the 2004, but I had (exactly) the same problem, caused by these wires being loose. It's worth a look, especially as loose wires here can cause an intermittent problem.

 

Cleaned cables and tested fuel pump voltage. it starts up when pump is hotwired and runs but i get a restricted performance signal. then i check codes and i get a Fuel pressure sensor code. High pressure. High since pump is running constantly. If i take off hotwires pump will run for 20 seconds and voltage will drop till car stalls. What sensor or module feeds info to keep voltage up?

 

also installed new Fuel pressure sensor. Nothing... someone told me crankcase sensor feeds fuel pump? True?

 

I have seen no mention of the fuel pump relay. On one of my other xk8s the car would run fine and the suddenly stop with no pressure at the rail. It turned out to be the fuel relay overheating.
Take a relay for another componet you don't need and see if that will solve the problem.
l attached the electrical manual for your car.

http://www.jagrepair.com/images/Auto.../jagxk2003.pdf

 

I believe the fuel driver module is replacing the relays?

 

Sorry. I haven't worked on an xk8 newer than 2001. It figures that Jaguar would add something else to the car so it makes it more difficult to diagnose.
Yours is an 04. I bet that by now they have sensors in the seat that when you fart it will throw a code.

PU1000- Excessive emissions driver seat.
. Cause- Eating too much chili beans
. Solution- Roll down the window

Just a thought.🤔

 

The code book talks about the Fuel Tank Pressure sensor (seems to be located on the access panel on top of the tank) and the Injector Pressure sensor (end of the fuel rail, passenger side). Your earlier code P0453 refers to the FTP. Maybe the fuel pump stops if there is a reading out of range. Remember, this is a return-less system. The fuel pressure is feedback-regulated by the IP sensor. FWIW, the fuel pressure is available over OBDII as a standard PID. Should read 55psi pretty consistently.

 

O man, after 4 solid 8 our days! I found it was a bad schematic showing the red wire as ground and the yellow red as positive on the fuel pump. it was running in reverse!!! changed leads and taa daa!!!

 

AWESOME!!! So to be clear- it WAS a bad fuel pump or the broken wires?

 

well a bad pump started the fiasco, and wiring it in reverse finished the plot.