When car is cold its recently developed an issue of only cranking. After trying a few times it starts. Once warm it starts right up. Any ideas what may be happening.

 

XJR you mean?

first suspect would be failing fuel pumps with the secondary already failed.

don't know what you mean by cold in relative terms.

 

According to a previous post it's an XJ8 so i've updated the thread title.

SteveyD1 needs to add his car details to his profile, otherwise it will be very confusing for people...

 

such as me

so ... intermittent operation of the only pump.

 

Wouldn't temp sender effect cold starts?

 

I had similar issue that the car 04 XJR would not start. Turned over, spark, fuel pressure all good NO codes!! Many frustrating hours over a few days it finally came down to being coolant had seeped THROUGH the sensor into the connector coroding it ( no visable leaks).
New sensor and connector pigtail (NAPA sourced) changed. Started right up first turn.
ECU needs to know engine temp apparently as a given to do anything!!

 

There is a specific fuel injector relay on the V8

You can jumper the fuel pump relay and see if that helps

Bore wash condition of the cylinders?