Could it be that I have no cats like I said it only does it when car is warm and driven or is it tps what you think I was getting service soon light on and off when the rpms started malfunctioning and it gave me a tps code?
Well a knock and throttle but I noticed when it started knocking only when the car is warm and driven the rpm gauge would o up and drop when on the freeway also it was around the time my cats went bad I cutt off and replaced with pipe now when u say wiper value your talking about the metal...
20psi at idle still is low who are I know more than you my friend cause before my grand national I was the mustang man and never seen my oil psi that low lol