2000 XJ8 Starting Problems

[skawtland]

Well, our 2000 Vanden Plas has been off the road now for about 3 weeks. She cranks and cranks, but will not start. She doesn't even try to start, all she does is crank. We have had a new fuel pump fitted, as well as a new evaporative loss flange, link lead, seal, and new sparkplugs, but still the same thing.

Does anyone have any idea what the problem could be without me having to resort to take her into Jaguar? I am going to replace the fuel pump relay, but I do not know which one is for the fuel pump in the trunk fusebox. Also, I have tried and tried to find the inertia fuel shutoff switch beneath the passenger side fascia, under the glovebox... but I cannot for the life of me locate it to see if it has been tripped.

I know another possible reason for this non-starting could be the immobiliser malfunctioning and staying ACTIVE and thus telling the fuel pump relay to keep its mouth shut, so to speak, and not relay power to the fuel pump, but is there any way to check for this personally? Or again, is that something it needs to be hooked up to a Jag computer to do?

Any help would be appreciated, as I am at a loss really. The Fuel Pump Relay was tested as good by our mechanic, but I am not going to put too much faith in him anymore, after charging us so much money to repair the car, then returning it in the same condition it was in prior to him taking it.

Here are a couple of photos that may be of help, one is off the trunk fusebox and the other is of the area the inertia fuel shutoff switch should be. From what I have been told, the inertia switch is a black box, about the size of a cigarette-pack, with a push-button type device in the top. I have looked and looked some more, and for the life of me cannot locate the bloody thing, so any help on that and which relay the fuel pump is, I would appreciate greatly.

Thanks guys,

Scott

 

[Radford]

I confess I am not much up on these cars, although I've had a buthers at my dad's XK8. I have two suggestions one simple and one diplomatic.

First the simple. Did you check the fuel filter? I know it sounds rater dumb, but you can always hope it is the simple things.

The second, or diplomatic solution is that you call up the dealership or a Jaguar specialist in your area, explain your problem and ask them where to look for these devices. Chances are they'll not only give you the information you require but that they'll give you some hints about what else to look for. I've always found that taking a twelve pack of beer to a mechanic on a Friday afternoon can really help the process.

 

[John S Farrington]

The problem may be quickly solved on a 2000 model by hooking up to the Jaguar proprietary software. Stopping short of that, you may resort to the old fashioned methods applicable to all internal combustion engines. Check to make sure it is getting gas and ignition spark. Break the gasoline fuel rail feed line and see if it pumps gas when you try to start. You can go a step further and hook up a pressure gage to determine fuel rail pressure. It should read between 35 to 45 psi. If it doesnt, it is probably the fuel pump or its relay, or the fuel pressure regulator. Its probably not the filter since they dont fail with complete stoppage (usually). Next see if you are getting spark to the plugs. Take the coil off or one of the plugs and hook up a conventional spark tester to see if it is happening. If no spark is present upon cranking, you have an ignition problem like like an ECU, crank position sensor or cam position sensor. You should also determine if the fuel injectors are being pulsed upon cranking. There is a small injector tester that can be used with your 2000 model, as well as previous models,to determine if the injectors are being pulsed. It is a light that triggers on twelve volts. If you dont know where to locate these components, take it to the dealer. I hope this advice bails you out of the problem. I will gladly offer more advice depending on what you find on these tests. Best regards, Jack Farrington

 

[skawtland]

Let me explain how she stopped running in the first place... 3 weeks ago she was running great... as usual. I took her up to our horse barns which is about a 1-2min drive up a very steep driveway. I parked her, turned her off. Fed, watered our horses, etc, etc... 30mins later I came out to start her, and she wouldn't start.

I really believed she was flooded, as is a common problem with these cars, but after trying and trying with the accelerator pedal down, then up technique, even taking out the plugs, and squirting a little oil into the cylinders... nothing, so I figured it could not be the old "stalling" issue.

She was at the local garage, and the guy did spark, compression tests etc., as far as I am aware, and everything was fine, which leads me to believe it is an electronic component failure, such as a sensor, etc.

As for the fuel filter... new one fitted with fuel pump. So I am at a loss really. I still cannot for the life of me locate the inertia fuel shutoff switch!

I really know very little about these cars, and what I have learned these past 3 weeks, in regards to the fuel system is pretty much it!

John, is there a place I can purchase the Jaguar Proprietary software to use at home with a laptop for instance? I have a JTIS Manual on CD-ROM I bought on eBay, but I have to say I am not impressed with it at all, it has very limited information on the 2000 model XJ8... perhaps I got jipped, who knows!

I was hoping to have a go at her on my own, if it is something simple, but I really think I am in the process of biting off more than I can chew with the kitty!

I REALLY do believe that it is something simple that is preventing her from starting, such as a sensor, telling the ECU not to allow engine turn-over. Everything mechanical seems fine, so I really don't know.

I think I will have to break down and take her to Jag... although I really don't want to!

Scott

 

[John S Farrington]

Scot, I have the Jaguar software pckage and it comes with a scanning hardware system. As far as I know it is the only available source besides the dealers set up and will cost about $2500. It is available through Coventry West. If your check engine light has been signled, the software will provide a good fault code to find the trouble. If the check engine light was not turned on it is not of much help. Without the check engine light, you must use the fault isolation procedures that I described above. Since the ignition signals have some redundancy as to how they are created, I would bet that you have a fuel delivery problem such as fuel pump relay, fuel pump or pressure regulator. A failure of one of the fuel injection sensors like temperature sensor or air mass meter could also be the culprit. In this case there is nothing like component substitution to identify the problem. That is why the Jag dealer has the advantage with his parts department close at hand. The age of the automotive ECUs and electronic sensing has fundamentaly changed what the owner can do unaided. Thank government legislation that mandates OBD2 for much of this evolution. Best Regards,