what causes car not to start right away? on 2001 Jaguar XJR

everytime when starting car.

Asked by for the 2001 Jaguar XJR
Check the timing, and the fuel pressure. You might be getting fuel but not enough to open fuel injectors, until it builds up.
1 more answer
Many things, one of the common one is fuel drains back to the fuel pump due to a failed check valve therefor it's not immediately available for the injectors.
Try to turn the key to the ON position several times before you try to start it to prime the fuel lines and see if after it will start right up.