My 2001 Jaguar XJ8 will not start when it is below about 40 degress outside. A fuel pressure gauge on the rail reads no pressure. Checked the relay and fuse in the trunk and they both work. When it warms up outside it cranks up and runs perfect.
Won't start in cold weather on 2001 Jaguar XJ8
So when it's under 40 degrees, the engine is cranking over, and the fuel pressure is zero? Have you checked for any trouble codes?
The problem got much worse and I was able to troubleshoot the problem to a failing fuel pump. I replaced the fuel pump and the problem has been solved.