Am helping to fix up an L reg Primera for a mate, needs new brakes exhaust and whole load of other stuff, easy to do stuff. We're Having trouble with the engine idling at high RPM, its a 2.0L single point injection. We have had the throttle body to pieces and cleaned the AAC valve, and the FICV and all other bits and bobs on the thing. Also cleaned a small piston type thing that seemed to be jammed, near the throttle potentiometer. Its now idles a bit better at 800 rpm but once it gets warm it idles at 1200-1500 rpm. Then if you turn the engine off then on again a few mins later it idles at 800 rpm again, no problems. Anyone got any ideas ?