Q: engine cranks will not fire, why?

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car will crank but not start when hot, new coil pack plugs and wires, batt. good, not getting fuel to fire up. took to autozone and codes came up for transmission temp sensor, and fuel evaporation sensor. when car is cold it will fire up and run ok, after some time will idle weird and has stalled to not start again when parked until cools down. any help is greatly appreciated thank you.

My car has 113000 miles.
My car has an automatic transmission.

My best guess would be the crankshaft position sensor. I have seen this part fail before without setting a code. It is located on the left side of the engine block, (front of car). It is near the exhaust manifold so it is exposed to more heat than in other locations. It can be replaced with the car on the ground, and nothing is really in the way to access it.

Sometimes you can see that the wire harness is coming apart very close to the sensor to verify it is bad, but with your symptoms, I would just replace it. The codes that were stored do not effect the engine’s ability to run, but you may want to have the codes diagnosed after the engine is running properly. Once again, this is an educated guess. There are some other less likely issues that could cause this. If you would like a professional to inspect your vehicle for you, a technician from YourMechanic can come to your home or office to diagnose your engine misfire and replace your crankshaft position sensor if necessary.

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