Out of the blue, after great period of service, sudden spikes of heat bleed off enough coolant to cause serious overheating while she's driving. I bring the car home and while I'm driving it the temp gauge is spiking to max even after shut off and coasting... first two thoughts are pump/stat failures, but the initial behavior is indicative of air in the cooling passages inside the cylinder head around the sensor. Is there a simple test possible to eliminate a cracked cylinder head without tearing apart the top end?
My car has 127000 miles.
My car has an automatic transmission.
The cooling system can be pressurized, using test equipment, and if no external leaks appear, yet pressure drops, that is an indication of an internal leak of the sort you are referring to. Such a leak could be from a defective head gasket, crack in the block and so forth. If no leak, external or internal, is found then a routine overheating diagnostic would be performed to pinpoint the cause of the overheating. If you desire that this problem be diagnosed by a certified Mechanic, dispatched by YourMechanic right to your location, please request an engine overheating diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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