The video shows the problem. The ignition doesn't seem to turn off often when the key is removed and also doesn't turn on often when trying to start the car.

https://imgur.com/a/l2ZMz3G

Any help would be appreciated.

 

Kev, no audio in that video right?

Let's focus on your issue. It'd work better if you asked questions. Give us background.
You pointed to two incompatible issues: won't start / won't shut off.

Can you see the incongruity? Can't possibly have both, please untangle your situation & request for us.

Can't shut off? Stab in the dark- you know you can open the fuel pump relay right? You tell us, does that leave the entire ignition circuit energized? Disco the battery terminal.

Come back with specific questions, history, descriptions please.

John

 

Is the door in the ignition lock closing when you remove the key? Try and lubricate the lock if it's not with some ignition lock lubricant. If it's not that check all the wires under the steering column that they are wired up correctly. Someone else has experienced a similar problem, they had wires near the throttle body rubbing and shorting so check there as well. Check the relay boxes to see if there is water in them and check the on on the passengers side because those are prone to water damage. There is a fuel cutoff in there as well so check that. I think it's most likely that a wire is rubbing and has rubbed the insulation and is shorting out somewhere. You will need a flashlight and look really closely. If all else fails you can go to Jaguar as they have some good software that can find these problems fairly easily.

 

Not sure if this is the part that you'd replaced (title of post) but there is a little gizmo pictured below that is the actual THING the key turns to engage and disengage the various positions when going through position i,,, ii,,,, and iii... The barrel and tumbler will STOP the key from turning when locked if the key doesn't match, BUT if the key matches and the red thing below is defective,,, well, you get the idea...

There is a little shallow notch in the gizmo below that accepts just the very tip of the key for turning on/off and everything in between.

 

I have the exact same problem on my 2001 XK8. Engine cranks but fuel pump won't turn on. I tried two different ignition switches, no change. I tested all relays, all good. No shop can advise and they don't want the dead car towed into their shop. Trying to get around to using diagnostic software. Hasn't started in years. Symptom was it wouldn't turn off and kept running even with key removed. I could shut off by disconnecting battery. If I reconnected battery, it wouldn't start until it sat for 24 hours.

 

Good Morning Man...

I'm interested in helping with this (as I'm sure others are). I'd suggest that you have two separate issues (or more).

In that,,, if it were me I would start a NEW and separate thread, as chasing your issues MIGHT take the original posters thread in a whole other direction. Start a new thread

 

You're absolutely right, this was lazy posting, my bad.

The two issues are both intermittent, so sometimes the ignition won't come on and other times when it does come on and start it then won't stop; have to engage the starter to kill it which makes me cry every time! Can you tell me which one is the fuel pump relay for next time?

I've now replaced the ignition switch twice so its not that.

Any other suggestions that would cause this behaviour? I don't believe there's anything aftermarket on the car.

 

Ignition door is closing fine. Wires seem fine and I've now replaced the ignition switch and no change. No water in the relay boxes. Fuel cut-off/inertia switch seems fine. I'll keep looking for faulty wiring.

 

Yep, replaced that twice now and no luck.

 

Yeah sounds very similar. Did you do all the above diagnostics I assume?