VERY FEW miles on this. Was experiencing high idle when car reached full operating temp. Had to "pop" accelerator pedal with foot to get the car to return to regular idle when at full operating temp. I did not have coolant pass-through hooked up though, but I am not sure if a plate or the shaft is dragging at the higher temps. Removed from '89. I told Summit about this and they told me nothing was wrong with it.