Q: overheating 120 minutes (or more) into vehicle operation signs of cyliner head crack?

asked by on February 18, 2017

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.

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