My XJS was sitting for a few years and yesterday I got it started.
It ran for about 10 minutes, just long enough the get me half way to the gas station.
I had it towed back home and started troubleshooting the fuel system.
I disconnected the fuel line from the pressure regulator to the rail and found fuel in the rail.
I disconnected the line into the regulator and tried cranking the engine to see it I was getting fuel.
No fuel to the regulator.
I blow low pressure air into the line back to the fuel tank to see it maybe the line was clogged.
It doesn't seem to be clogged.
I suspect the fuel pump is bad.
I have a Jag XJ-S Service Manual (AKM 9036 and Supplement AKM 9063BB) but the instructions to renew the fuel pump does not seem to fit the 2+2 convert.
Does the fuel tank have to be removed to renew the pump?
Is there another Service Manual that covers the 2+2 convert?

Thank you for your time.

 

The relays you asked about in your first picture should be for convertible top operation.

 

It is best to clear and check the fuel system starting at the tank and moving forward. Certainly, by blowing compressed air backwards through the filter you may have clogged the filter. Disconnect it and blow from the engine side of the filter forward.


Then check to see if you have fuel to the filter from the pump, and if not, if the pump is running or not. If not running, check for power to the pump. If power and no pump action, look at the pump - which I believe on your model may require moving the tank.
Greg
Greg

 

LuvmyXJS',

All six relays control the convert top?

According to the Service Manual I have, there is supposed to be a relay for the fuel pump in the forward right side of the boot.

Is there a relay for the fuel pump somewhere back there?

Also, do you know where I can get a good copy of the electrical system schematic for the 95 AJ16 2+2?

Thanks for your help!

 

Greg in France,

Where and what colors are the power leads to the pump?

The electrical schematic in my Service Manual is unreadable and it deosn't address the 2+2 convert with the AJ16 4.0L.

Do you know where I can get a good copy of the electrical system schematic and Service Manual for the 1995 XJS 2+2 with the AJ16 4.0L?

Thank you for your time.

 

I am sure that PTJS1 and other facelift 6 cylinder experts can help you on that, I am afraid my experience is limited to pre-facelifts!
Greg

 

Electrical guide is here: http://www.jagrepair.com/images/Auto.../jvs1995en.pdf

Yes, the relays are for the top and side quarter windows. One each for up and down.

Fuel pump is in the tank, the wire from the ECU controlled relay is blue/red.

In your second photo that is the positive battery cable that goes forward.

 

The Parts & Service Manual that you need for the late facelift 4 litre is JHM1143. Jaguar have a sourcing problem on the DVDs at present so you might have to buy a 2nd-hand copy. Don't think about running an XJS if you haven't got the right manual.

There is one (at least!) error in it insofar that it says that the fuel filter is located underneath the left rear wheelarch, whereas it is located in the rear corner of the front left wheelarch behind a plastic cover panel.

The fuel pump relay is tucked forward in the right front section of the boot after you've removed the right boot trim panel. I think it's the silver relay but might be wrong. I'll try and check tomorrow.

Don't condemn the pump yet. It could be, but my money is on a blocked fuel filter or sediment in tank, particularly as the car hasn't been run for a few years. Can you hear the pump running for few seconds when you turn on the ignition?

Good luck

Paul

 

ptjs1,


Thanks for the info. When I turn the key to accessory or start, I do not hear the pump start.


Before I parked the car, I had problems with it stalling and after the stall, it would be difficult to start unless I let it sit for about 30 minutes.


I was told to replace the crank position sensor which I found had a corroded tip. That doesn't seem to be the issue.


Is it possible to bypass the ignition switch and put 12VDC directly to the pump to check if it will run?


Thanks!

 

zombiewoof,

The fuel pump relay is a silver one with a yellow base, and the 20a pump fuse is no.12 in the RH rearward fuse box.

Paul

 

If I am not mistaken the crank sensor if failing would stop spark but not fuel. Did you replace the crank sensor? The reason why I ask is the magnets in the crank sensor over time can get weak from age and stop reading correctly. If your crank sensor is original would be wise to replace it right away.

If you can not hear the fuel pump run for a short time when you cycle the key on chances are your pump is the issue or at least a power issue to the pump. Best to test for power to the pump when you cycle the ignition key-if you have power to the pump but pump is dead it would be time to get a new fuel pump.