Q: Car will not start when the engine is hot.

asked by on March 02, 2017

Have bypassed the security system fuel pressure is good thinking my crank sensor

My car has 18000 miles.
My car has an automatic transmission.

Hi there. If there is fuel and the engine will not start up when it is at operating temperature, then either the crankshaft position sensor is getting hot and not making a connection or the coolant temperature sensor is malfunctioning and letting the computer think that the engine is overheating. If you need further assistance with your engine not starting when hot, then seek out a professional, such as one from Your Mechanic, to help you.

Hi there. If your crankshaft position sensor is damaged, it would probably not allow your car to start when it is cold. Perhaps we are reading your question incorrectly, but if the car doesn’t start when it’s hot, it is caused by a ignition or fuel system component failure. Most of the time, this is due to mass air flow sensors, EGR valves or fuel injectors that are dirty and need to be replaced or cleaned. The best way to determine what is causing your issues, you might want to have a professional mechanic come to your location and complete a car is hard to start inspection.

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