91 XJ6 Sovereign will not start
 

My 91 Sovereign will not start. I just put in a brand new fuel pump. I am getting good spark, but not getting an fuel to the motor. I disconnected the fuel line and tried starting the car to see if I was getting any fuel delivery at all, but there was none. All of the fuses in the car are good. I checked the inertia switch and the fuel pump relay, and both appear to be functioning properly. I tested the wiring at the harness inside the trunk and there is proper voltage on the positive (blue/red) wire, but no reading at all on the negative (black) wire. The wiring was tested while my wife tried starting the car. I thought maybe that meant there was a bad ground, so I cut the wire and grounded it inside the trunk, but this did not change the no start condition at all, so I reconnected the wire. It has been suggested to me that maybe the Crankshaft Positioning Sensor was bad. Would this cause the fuel pump not to run, or is the problem somewhere else? Please help, because I am completely baffled as to what the problem could be. Also the VCM is giving me a code "PAO" but nobody can seem to tell me what that code means.

Yikes. "PAO" is actually "PAD", which means that one of your two brake pad warning sensors is open circuit. Unrelated fault for another day.

I am assuming that when you checked for power and ground, and when you jumped the fuel pump to an alternate ground, that you were working at the terminal connections on the evaporative loss flange, i.e. the big cap on top of the tank. That means that either the new fuel pump you installed is DOA, or the terminal connections on the underside of the evaporative loss flange, where the fuel pump wiring link lead connects, are cooked. I'll try to attach a picture below, my bad if it doesn't fly.

The crank position sensor has nothing to do with fuel pump operation, and I wouldn't be asking those folks to help you sort out your brakes either. A bad crank sensor will inhibit both injection and ignition system operation, but the ECU switching circuit for the pump relay will never know the difference.

There is an intermediate connection in the two wire harness that goes up to the evaporative loss flange connection for the pump, follow the wires down and I think it is adjacent to the LH fuel tank retaining strap on your car. These terminals can also fry and go open circuit. I don't think you have reason to look at anything other than the areas I mentioned.

Pics
 

Trying again

link lead question
 

When I replaced the fuel pump I could not remove the link lead wiring harness from the inside of the evaporative flange. It was completely seized on. After getting everything put back together and getting no action from the new fuel pump, I had an idea that the link lead harness might be fried because of the trouble I had removing it. I called my local Jaguar dealership and they told me that they can no longer get that harness, and they gave me the number to British Recycling in CA. They told me that they have the part but it will cost me $180 with shipping included. I don't know if you are familiar with them, but they are basically a foreign car graveyard, and the reason it will cost so much is because they would have to pull that harness from a few cars to make sure that thay send me one that will work. Do you know of anywhere else that I would be able to get that harness from that won't charge me so much. I am currently unemployed and can't afford to spend that kind of money. And I need to get the car fixed so I can find a new job. Any information you could give me on where I might find that harness would be extremely helpful. I am going to try my local junkyard because they actually happen to have 1 XJ6 that is a late VIN 91 like mine, but if it doesn't have the harness, I'm screwed.

can I "hotwire" the fuel pump?
 

I checked my local junkyard today, and the Wiring harness for my fuel pump was already gone :( Is it possible for me to bypass the wiring harness at the Evaporator flange and wire the actual fuel pump directly to the outer harness inside the trunk? I know that if I do this, I can seal everything off so that the system can properly pressurize. My only concern is any possible safety and/or functionality issues that this might create. I would only do it as a temporary fix until I can actually locate and afford a new harness, so the car would not stay like that forever. Is this a reasonable temporary fix? If not, please let me know if there is anywhere that I might be able to get this harness relatively cheap. The only price I have found it for so far is $180 and that is WAY out of my budget. Thanks.

try coventry west in georgia, www.coventrywest.com
1-800-331-2193 ext 120

that will get you to a man by the name of pete bond, and he will be able to help you out, hopefully for cheap. They're a huge jaguar salvage operation, but also sell new parts, so they may be able to get you a new harness from an aftermarket distributor, which would bring the price down a good bit since they wouldn't be pulling a part out of a car, but rather would be pulling a part off the shelf. worth a shot. if not, wire it to the battery with a switch in the dash. that works for everything.

Ok i have a 88 xj6 the car has low miles runs near perfect, about a day ago i was drive and it just killed. So I coasted to the side of the road shut it off and it restarted without a problem. The next day it ran fine no problems,then today it did the same thing but it didnt start back. I had to have it towed home, when i got it home it started again ran for a while,I turned it off. Tried to start it again no start, I check the relay and i have power there and the relays good. So i go to the trunk I have very weak power at the upper harness. But then it will not and then go to full power and the car will crank. SO i go under the car check at the fuel pump no power,I can hear the fuel pump when if it comes on. I changed the fuel filter, I need to get this car running A.S.P. Can i by pass all the wiring for the fuel pump run new wires and a switch to turn it off and one when i run the car. And if so what is the danger or is there any if I do the wires right I have 90 bucks to my name and dont get paid for 2 weeks. I just need to get back and forth to work and have no other way. Any help would be welcomed I am going to fix it right in the next few weeks but for now is it ok to wire it this way.