Q: Can an overheated engine cause my car to not drive ?

A blown head gasket may cause a number of different symptoms. A head gasket that fails between cylinders will generally cause a misfire and potentially compression leaks from one cylinder into another. Low compression will eventually result in a rough idling engine. Damage of this type may not cause overheating, coolant in the oil or any other outward sign. Many people overlook this as the cause of engine misfires, because the blown head gasket does not also give the other more common symptoms such as steam coming from the motor or from the exhaust. When the head gasket fails between a cylinder and the coolant port, coolant may leak into the cylinder causing it to be burnt with the fuel charge in the combustion chamber. This often results in misfires on startup, especially after the engine is run, turned off and restarted. This type of failure may not always show with a compression test. I would recommend having an expert from YourMechanic come to your location to properly diagnose the symptoms you describe.