whey iam i loosing power on accelaration and its show egine falut. on 2003 Jaguar X-Type

i have not change my oil in five months but i did change my water pump, the radiator, the spark plugs and all the gaskets associated with it.

2 answers
Sounds like you have an Mannifold intake air leak. Take a look at http://www.2carpros.com/questions/jaguar-x-type-2004-jaguar-x-type-imt-valve

Also, take a look at http://forum.roadfly.com/threads/12667740-my-x-type-projects-and-mods/page4 (Towards the bottom, quote 75)
accelaration and its show egine falut