Q: Could my compressor be affected by a bad thermostat? 2007 Infiniti M35

Hello - new thermostats are electronically controlled, primarily to be sure they are getting the engine up to operating temperature quickly. As such the thermostat and air conditioning compressor are separate components, and failure of one or the other are unrelated events - and repairs. However, the HVAC control on your dash does control both - and it is possible that there is a problem with the control turning On/Off the AC compressor. I recommend a thermostat replacement to repair the known thermostat problem, and an AC isn’t working inspection to check out your possible compressor problem. Both can be performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, repair and diagnose these problems, and give you an accurate assessment of damage and cost estimate for repairs.

The thermostat should not affect the A/C compressor blowing cool air. The thermostat regulates the flow of the coolant in your car’s engine and controls when the coolant flows in and out of the motor from the radiator by opening and closing at specific temperatures. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. When the thermostat is stuck open it can cause the coolant to circulate constantly resulting in the motor never reaching the correct operating temperature. The reason the thermostat can affect the heater is the coolant flows through the heater core which uses the warm coolant to blow warm air into the cab of the vehicle. This is why the heater may work intermittently depending on the operation of the thermostat. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your car.