i literally just changed out my thermostat for what ever reason it was different then the factory therm. so i had to do slight fabrication to the therm. cover nothing major that would effect the seal but now i have a restricted performance light out of no where...i pulled the codes and these are the codes that popped can anyone tell me asap what they are p0455,p1000, p0327

 

P1000 is a nothing to report code,
P0327 is knock sensor A Bank voltage low (bad connection or sensor)
P0455 is a fuel cap fault, try re-fitting it after clearing the codes and see if it comes back.

There's a how-to on replacing the knock sensors here,
https://www.jaguarforums.com/forum/x...ine-faq-45963/

Neither are coolant circuit related, but you could have missed connecting a knock sensor back up?
Hope this helps

 

real random idk if something got wet wen i flushed out my radiator but i drove it tried a few places to get it checked came home posted these codes and then went back out started it up and all the codes were gone