Hi Guys, I'm having some grief with an S4 at the moment, the car has been REVO'd and is standard other than that. At around 3000rpm i'm getting a bit of a kick back, not sure what the problem is. I'm going to replace the ricirc valves with forge ones. I've had it down Mosley's garage and when he performed a live data stream read on it, it hits 20psi and intermittently drops to 17. He suggested soft or sticking actuators. Has anyone ever had this problem or can shed some light on it? I dont want to play with the actuators if theres only a possibility that its them, engine out is expensive!!