Jaguar hard to start cruise not available

My jaguar is hard to start alot of noise in engine knocking noises I have to hold gas petal down just so it will isle for 15 minutes before it will idle on its own without dieing even after car is warmed up it acts like it don't want to break when I back up or take off after its warm says no cruise control lights flicker in the car sometimes the heater will shut off while I'm driving then start back up or it won't work it does not get cold after driving for a while it straightens itself out and the engine runs smoothly until I park the car and let it sit for two hours then try to start it and I have to repeat the same process again to get it started it has to warm up for at least a hour before I can take off safely without wondering if the breaks will give me problems when I try to stop. Cruise control still not available. Can someone please help me.