Overheating at idle only when A/C is on

Hi,

If the engine only overheats with the AC on that is normally caused by an excess load on the engine. This is caused by a failing AC compressor that is bogging the engine down, a plugged radiator condenser fins, or a water pump that is failing. It can also be the fan but let's assume that is ruled out because you changed out the clutch.

I would suggest using a can of coil cleaner on the condensor/radiator and then spray through it with a garden hose. If you hold the hose pretty close to the front of the condensor/radiator, you should be able to see a pretty decent amount of water coming through the other side.