Definitely not the thermostat, but it is likely not opening. White smoke from the exhaust is due to engine coolant burning in the engine due to a leaking cylinder head gasket, or less likely, a cracked cylinder head. Combustion gases will pool under the thermostat and prevent it from opening. Thermostats need to be hit with hot liquid to open. Hot air won't do it.
Thursday, April 24th, 2014 AT 3:08 PM