I am starting to have the same issue with my 2005 XJ8L - As the temp has started to drop below 0 Celsius in the AM, It cranks over a long time before catching. This just started over the last few days. I did a forum search and came across this thread. Yesterday morning I tried the 10 second wait and it started immediately. Not sure if it was coincidence or not - If that continues to work, what should I be looking for? Or should I just continue to wait the 10 seconds?

Thanks for any advice/guidance

Cheers!

 

At a guess, Gus was looking for signs of weakness in the fuel system. For example, a weak fuel pump or the fuel rail not holding pressure when off.