hey guys got a bud who has a 95 cobra with basic bolt ons. problem is the car idles rough and when you rev the motor it dont do anything for a moment or two then it finally revs but busts up real bad and when you let off the accelerator it revs and thats when it busts up. he took the whole intake system off from the filter to the intake manifold to clean out carbon build up put new gaskets back on and now he has these problems. has no vaccum leaks we checked by spraying starter fluid over vaccum areas and the intake manifold to see if it ran different. he left the distributer on so we dont think its a timing problem. all hoses and plug are plugged in. so any inputs would be appreciated. thanks guys