Engine cranks when hot. Why doesn't it start?

once had the same problem the armature in the starter expands when hot and wont crank cools down and starter works

You need a motor. If it overheated and stalled as a result than you cooked the engine.

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Many cars nowadays have sensors built in to make then run economically and reduce pollution. If you start you car for very short runs, after a while these sensors become fouled, and/or they shut down to protect the engine.

Without diagnostics, I can't say exactly what the problem is but, I would suggest the next time you start the car, you give it a good run and get the engine good and hot to burn of any deposits stuck inside. (about 40 miles). Assuming this works, give you car a good run, 20 minutes, at least once a week.

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If he installed a new or remanufatured starter, I would suspect a weak battery possibly. If he installed a used starter, I would say the starter is bad. A hot engine is harder to crank than a cold engine and if the starter is marginal it will act the way you described. Try boosting your vehicle the next time it's hot, or get your battery load tested by a reputable shop that doesn't sell batteries. I have had experience with remanufactured starters that were no better than the unit I removed from the vehicle. Have him get a second reman and see if that doesn't solve the problem.

If the fuel pump is still making a noise and the engine doesn't start when hot. Possibe Crank Shaft Position Sensor. (not real nice to do) Can also be the ignition module but more often its the Crank Sensor. There are some simple tests if you are handy with cars?

If this problem only occurs after shutdown when hot, check temperature sending unit. This is usually first thing to prevent starting until engine is completely cooled down.

Does the engine turn over? If it does, then check to see if the check engine light comes on when you turn the key to the on position. If it doesn't, then the PCM is not receiving power. Check the orange power wire usually located by the battery to make sure it isn't damaged. Repair if necessary. If the check engine light comes on when the key is turned to on then crank the engine while observing the light. Does it go out while cranking? If it doesn't, then a problem with the crank sensor signal is indicated. If it does go out then the problem might be fuel related. Disconnect the air cleaner hose to the throttle body. Have someone crank the engine over while opening the throttle slightly. Spray starting fluid into the engine to see if it tries to start. If it does then a fuel related problem is indicated.
CAUTION : Wear safety glasses during this procedure. Be careful around moving engine parts.

I suppose that you mean it starts but doesn't continue to run. And if you try to start it right away it'll just crank. The fuel pump is on in crank but not in run ( maybe ). Find the fuel pump relay in the underhood fuse relay panel and use a test light to cheak the pins for power and ground. First with the test light hooked to a good ground, check to see if it works first ( touch the battery positive ) then touch all the pins of the relay ( removed ) One should be hot all the time ( if not the fuel pump fuse is blown) another should be hot with the key on. one of the others will be hot only in crank ( this is the fuel pump) The last other is ground with the engine running after started. The one thats hot in crank put power to it with a jumper wire and start the engine ( it'll run ) the fuel pump also gets turned on by the oil pressure switch and the fuel pump fuse is blown it'll also not run the engine. But it'll run right after it's cranked and quit

THIS PROBLEM IS ALMOST ALWAYS DUE TO A FAILED FUEL PUMP PRESSURE CHECK VALVE, REPLACE THE FUEL PUMP.