05 mini 1.6 petrol
 

When im driving my mini if i push on the throttle hard it revs high but dont move tht fast if i let off and press on it picks up but u hve to let off nd on constant there no blows no over heating as a k&n on nd pipe its attached to is abit taped up but crnt really see it been the problem any1 have any ideas i am gunna change air box and try that