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Q: Occasional problems with the engine startup

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My car has been having starting problems lately. It used to happen occasionally when I drive it for longer than 45 minutes. Now, it occurs randomly and more often. It can be turned on again if I wait for about half an hour and try again. At the dealership, they couldn't diagnose what the issue is. Do you have any idea what the problem is and how to fix it? Thank you in advance.

There are a couple of things that come to mind. A faulty crankshaft position sensor has been known to cause this problem. Scoping the crankshaft sensor on a warm startup would be one way to determine if this is the case. Another could be a faulty ignition switch. Some powertrain control module functions turn on when the key is turned on, so if the powertrain control module does not power on, then no faults would be recorded.

As the switch warms up while the engine is on, the contacts heat up as well and this could be why the problem only occurs when the vehicle has been operated for a while. You may want to enlist the help of a mechanic, such as one from YourMechanic, who can read sensor statuses during operation to determine the cause of the starting issue and how it can be corrected.

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