My Mercury Mountaineer over heat replace thermostat and run fine but when ac on start to overheat turn it off and run fine could this part be what I need
Thanks
Verified Reply - Solomon
Hi Rick, I'm glad to help you! The AC condenser heats up as the AC is being used so the engine cooling system has to deal with this increased heat. Plugged or blocked radiator condenser fins, fans not working efficiently or a water pump that is not circulating coolant could all cause overheating with AC on only. However, without the presence of your vehicle we would not be able to properly diagnose it, nor provide you with a 100% answer. I would suggest that you take your vehicle and get it thoroughly checked by a certified mechanic.