My project last weekend was to eliminate a troubling rattle in my drivers side door which turned out to be an anti-theft device that was loose. I solved it with duct tape! All is quiet now. While I was inside the door I fiddled with the door locking mechanism. The next day she was running just perfectly, nice and quiet on a bumpy road. Then suddenly after a short drive and turning off the ignition it would not restart and the check engine light now comes on!

So my question is could fiddling with the door locking mechanism trip a switch in the Jaguar electronic brains and create a non starting engine?

i spent today following Gary VanRemortel’s XK8 Bible checklist on non-starting engines. The fuses are good. The battery has plenty of power. I did a hard reset. I checked the neutral safety switch as well as the security immobilizer and reset the initertia switch.

All were good.

i added extra fuel since the gauge showed just over a quarter of a tank, so to be sure the gauge was not faulty and I was not out of gas! I removed the cap on the Schrader Valve and released the pressure. Although there was no pressure to release! I listened for the fuel pump to start but could not hear it. I then sprayed some starting fluid into the intake. The engine started immediately but died a few seconds later.

I did an OBD2 scan on two different readers — icarsoft and on a wireless scanner on my iPhone. I could never get a read on the iCarsoft but I did get a P1000 on the wireless unit.

I fear this is turning in to the dreaded fuel pump issue, since the engine briefly cranked with the starter fluid, but wonder (hope ) it is instead fuel pump control module issue. Apparently, according to my research, beginning with 2003 models with the 4.2 liter engine, Jaguar changed the fuel system and the module. So is there a way to test this new larger control module? I find only module tests suggestions on the pre 2003 cars.

So I go back to my original question could my playing with the door lock mechanism on the driver side door have anything to do with this sudden starting problem? For what it’s worth the passenger side door does not lock when one uses the key to lock the driver side door. The alarm sets but the passenger side does not lock. Nor do either of the doors lock when one moves the shifter to drive. Frankly it was only playing with the mechanism that I learned you lock the doors with the key — not by pushing the key fob button.i just always thought setting the alarm was the door lock!

Anyway, replacing the fuel pump is more than I want to tackle so my next step unless another solution is found is a flat bed tow truck and a sixty mile tow!

Any thoughts would be appreciated and in advance I offer my thanks!

Bill

Bumpy road ....sounds like you triggered the inertia cut off switch ..Its in one of the dash fuse boxes ...black thing with a rubber button on the top ..push it in to re set. ( my RHD has it on the passenger side)

You can only tow a jag with the rear wheels lifted ..ie backwards but I think you mean a flatbed.

He did reset the inertia switch in post#1. If the ignition switch on does not result in fuel pressure it's either the pump fuse, pump relay or the pump itself. Probably the pump, since that's the most expensive option.

Yes pump $ 15 ......

To my knowledge there is no cheap option for a 4.2 fuel pump, only the 4.0 ones....

Hit refresh.

Seriously, the price of these 4.2L pump in new condition seem to have come down pretty dramatically. Check eBay.

The locks seem out of sequence, or something. I would disconnect the battery with the top down/windows down and reset the locks in the lock or unlocked position and see if you can get a change of action that way. At the same time, electronically, you may have disturbed something in the driver's door that signals the passengers door thru the door control module, to the BPM, then onto the passengers door.

I hate to say this but, I would remover the driver's door panel to run thru and carry out tests,,, just so you can get at things, have a look see and try to back track...

About the door and the SCLM etc... I just don't know. Did you say that if you close everything you CAN set and unset the alarm?

Bumpy roads are funny things. Especially with an old car. Believe it or not I've had fuses blow on bumpy roads.

Based on multiple posts in here, non op or fussy drivers door lock seems to be a source of problems. I always keep the top down. Maybe I should just climb in and out of the car w/o opening the driver's door to avoid disturbing the car's complex electrical system? Better yet, a cell phone controlled overhead hoist in the garage to lower myself into the car to start? Climb out as needed. Only use the passenger side door?

If the 4.2 fuel pump has to be replaced, is it necessary to do the whole "cut an access hole" thing or are there other options?

Cutting the hole takes about 5min, 10min tops. From there, removing the pump takes another 5, 10...

I would have to look at the ED but there is a way to bypass the VDO regulator, energize the pump while it's still in the tank to see if it will run,,, potentially meaning that it's something else... wanna know more?

Other option is to release the fuel lines from under the car, and a bunch of other things to remove the tank.

Yes! How would one “bypass the VDO regulator to energize the pump... to see if it will run” ? By the way, what is a VDO regulator?

Cool. It's not too tough, but let's be careful here.

Anyone hear any mistakes in my explanation just say so...

If you feel unsure or uncomfortable DON'T do this.
Just have a look see...first.

Confirm - your car is a returnless fueling system - post MY 2003. I've worked on my 04 XKR and I believe the 2003+ XK8 is the same. A returnless fueling system. If so,,,
The fuel pump regulator (FPR) receives info from the ECU about how much fuel (pressure) to provide to the rail (don't worry about all that right now) then powers the pump... The regulator is a little silver box on the RH side of the trunk/boot. Remove (as best as possible) the carpet cover covering the stereo and nav system and you will see it (see photo). There is a red (R) and yellow red (YR) wire coming out of it. It's as simple as melting back a little of the YR insulation and twisting a wire into what is exposed and finding a suitable ground.

With ground hooked up & key turn to on, pump should run full blast for 2 seconds (prime) AND continue IF the car starts.. I believe the car (ECU - fuel pressure regulator/FPR) shuts down/won't power the pump between initial key turn (prime) UNLESS the car actually STARTS. What you'll be listening for is the 2 second prime...

Once you ground that wire and turn the key, listen... If that doesn't give you a definitive, turn the key to start the car. If the car starts car will run rich, fuel pressures at the rail will be near 70 - so DON'T drive it - but DONT panic. There will be no harm. This is just to test to see if the pump works.

You could also tie into BOTH, the red (R) and the yellow red (YR) wires and apply 12v (neg battery terminal and positive battery terminal) right there from the battery just to see if you can hear the pump spinning BUT,,,, DISCONNECT the plug/connector on top of the VDO FPR before doing that... Just because...

Sounds simple enough! Will give it a try this evening! Thanks.

You might revisit the scene of the crime. With the key, lock the drivers door and wait to hear the chime and then unlock it listening for the chime. It may have shut down for security.

I'm with JR in this... I just don't know what in the security system would cause this... And how.

It was well worth the try, but unfortunately no change. So now to the suggestion of bypassing the FPR. It seems simple enough but your warning to not do if I am unsure or uncomfortable has my attention. Is there a downside or danger to doing the test?
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Thanks, unfortunately the fuel pump problem remains. When I locked the door with the key the chirp of the security horn sounded and I heard three faint but individual clicks inside the driver side door. When I unlocked with the key no sound. Holding the key to the right a little longer and the windows all roll down.

Thanks for the suggestion.

Bill

It was well worth the try, but unfortunately no change. So now to the suggestion of bypassing the FPR. It seems simple enough but your warning to not do if I am unsure or uncomfortable has my attention. Is there a downside or danger to doing the test?

No. Not really. The car won't like it (extra fuel, high pressure at the rail/bad trims) but I actually drove my car this way (super sparingly) until I solved my pump problem. As you can see in the wiring diagram,,, your just powering the pump.

I should add. This will indicate a pump problem only pretty much. If the pump runs/works it will not explain why you are not getting the "ok to fuel" signal from other systems in the car...

Okay did the test but cannot confirm the fuel pump started by hearing pump. I tried to start the car but also no success. I hooked a test light but the light did not light when turned on the key.

I also removed the blue cap on the fuel rail and pushed the the little air press type valve but no pressure or fuel was released.

Any thoughts on next step?

in advance, thanks.