having abit of an issue with my xjr,
most the time it starts right up, but on occasion it takes a while to get going, but always starts.
no issues with performance or MPG.

i dont have a fuel pressure tester, but after running it for around half an hour than leaving it for a few hours to cool back down,i poked a screw driver in the shrader valve and there was enough pressure to spray fuel out.

ive found instead of letting it crank and crank,
i can crank it for a few seconds, stop then crank it again and itll fire right up.

i hope its not a leaky injector, looks like the supercharger needs to come off?!

where should i begin?

 

Check for code P0340 Camshaft sensor different then the Crankshaft sensor which will start it but with more rotations .

Swap the fuel pump relay as it may be intermittent .

You have 2 fuel pumps on the " R " where the second comes on at 4000 RPM , but if the engine fails to start the ECU will turn on # 2

 

no codes stored;
ill get the relays swapped and see if anything changes.

 

so after abit if testing it looks like fuel pump no. 2 is out.
it doesnt run without the pump no.1 relay out, and at first it starting with a horrible sound comming from the pump when just the number 2 relay was in.

 

Someone mentioned the transfer to to the # 2 pump in the starting sequence does not accrue unless the # 1 relay is in .

Verified fuses are good circled in red ?

You can test the pumps themselves another way and bypass the pumps relay control circuit by putting in power straight to the pumps at the relay socket . High current arcing danger to the relay socket / base contacts so you would have to use blade type connectors on the jumper wire and your last arcing contact would be the B + power source either the battery or the large terminal stud .

Look for burnt sockets on the connectors on the pumps ( common ) and ensure they have good grounds along the side of the battery . There is something about a noise suppression harness before the pump connector that can be bad that I don't know anything about .

Bottom line if you have 1 pump out you might as well change out both while your there .

A new relay is needed when you change a pump because a failing pump will damage the relay .

There are alot of posts on both changing the pumps and what brand recommended worth looking at to save alot of effort like below for the like X300 .

https://www.jaguarforums.com/forum/x...quired-163902/

 

http://www.jagspares.co.uk/Manners/p...C2N3866%2F1%2A

am i right in thinking that both pumps are the same for the XJR so i need 2 of these?

 

Yes , the same and recommended .

There is a issue with the 2 in your case individual fuel check valves in them that someone would have more information on . If any check valves fails in a lessor pump you will have quick starting issues so I recommend getting advice on a good manufactured pump .

 

I replaced both pumps which didnt resolve the issue, needed doing anyway though.

I Checked the spark plug wells and found the first cylinder closet to the bulkhead on the drivers (us passenger) side had quite a lot of oil, and have noticed theres an ever so slight rumble at idle that dissapeard when i cleaned it, came back again after a while presumably as oil has leaked down again.

Seems odd that it doesn't throw any codes, just waiting for the gasket to arrive, hoping this is the cause of the starting issue.