The engine starts great and warms up nicely. Then, at tick over the revs seemingly randomly surge up to 1,200 RPMs, sit there for 30 sec then drops back to tick over! There appears to be no rhythm to it. It has revved higher at times. I have changed the idle control valve, the throttle position sensor and MAF sensor, but no change. I have checked for vacuum leaks as well as I can. It has started to randomly increase revs whilst under load now. I’m considering changing the Coolant Temp sensor and Inlet Air temperature sensor but not sure if I’m just throwing money away.
Sep 17, 2023 at 10:17 AM
