I cleaned my throttle body a couple months back and ever since I did the Cruise Control won't work and my throttle cable sticks and I have to kind of slap it after the car has sat overnight or for several hours. What did I do wrong?

 

The ECM adapts to the wear of the Throttle Position sensor. It's possible that your throttle used to be part open due to gunk that you cleaned out, and the ECM adapted to it. Now that you cleaned out the gunk, the TPS adaptations are wrong. I would start with resetting them using IDS.

 

Ok what is IDS? Do I need any equipment for this?

 

IDS is a piece of diagnostic software from Ford/Jaguar/LandRover. It requires a piece of hardware called VCM, which is a box with 2 cables. Once cable plugs into the USB port of the laptop, another one into the ODBII port of the car. Only the first generation (aka VCM I) will work for X300. I was told that second generation VCM (aka VCM II) won't work for X300.

I have a genuine VCM made by Rotunda and so far (knock on wood) it served me well. Some members had good luck with Chinese clones of the VCM, others didn't. YMMV

You can also use IDS with Mongoose by Drew Technologies. Mongoose plugs into laptop via USB and also into the OBDII port of the car. I was unable to get Chinese Mongoose clone to work with my X300. Some members had better luck with later model Jaguars. YMMV.