Why would the AC fan blow but not cool or heat the car on a 1993 4Runner?
Why would your central air conditioner blow warm air only in the middle of the day and blow fine at night?
Why would the front AC blow cool only on 2 but blow warm air on 3 or 4 and the rear AC blow only warm air?
Why would an ac intermittently blow cool air through the vents even though the fan appears to be working ok?
Answer Most air conditioners blow cool air at first till the pipes that carry the cool air turns cold, then you get the cold air. If you are getting hot air then perhaps your Freon is in need of re-charging. That would be a good first step in finding your problem. If after re-filling your Freon you still have problems you might want to check for leaks, but this is better done by Air Conditioning…
Anything that causes the engine to run hot, like a faulty thermostat, can cause the head gasket to blow. also say a coolant hose ruptures, all the coolant is then drained from the radiator and the engine is then essentially running with no way to cool down, gasket blows. there are many ways for the engine to run hot, but it is the main reason a head gasket would blow out.