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Q: Car starts then dies

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Ran a diagnostic no codes so what could the problem be. I replaced both crankshaft sensors diagnostic shows no codes still comes up clean

My car has 112000 miles.
My car has an automatic transmission.

A: Hello. Start by inspecting the rubber boot ...

Hello. Start by inspecting the rubber boot going from the air filter box to the engine. There may be a crack or tear in the smaller finger off of the boot towards the engine.

You may also have a mass air flow sensor that is reading low. You would need a scan tool to read this value. At idle it should be reading at least 4 grams per second.

You may have an air intake leak elsewhere which can be diagnosed by either using a diagnostic smoke machine to inject smoke into the engine to find a leak, or spray the engine with brake cleaner in various areas while it is running to listen for a change in the RPM to find a vacuum leak.

Diagnosing this problem will require a visual inspection and possibly advanced diagnostic tools. A certified mobile mechanic from YourMechanic can visit your home or office to inspect why your vehicle turns off and provide any necessary repairs.

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