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Q: Code P0340

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code p340 keeps coming back. the sensors that were changed where the one on the right and the front. I smell gas and car is running sluggish.

My car has 132000 miles.
My car has an automatic transmission.

Hello. Code P0340 sets due to many possible faults. The sensors themselves have to be tested using an oscilloscope to see if the output waveform meets spec. If the sensors were not tested, there may have been nothing wrong with them and that is why the Code has returned. DTC’s do not necessarily identify faulty parts. The only way to condemn a part is on the basis of a specific test procedure and diagnostic in the shop manual, wherein the specifications for the part will also be printed.

An expert can diagnose it for you to get the issue resolved promptly. Among the initial steps, you are to check the sensor wiring back to the ECM. If the crankshaft position sensor (CPS) is malfunctioning (it can be tested), such a failure could set code P0340. Code P0340 can also set if there is a fault in the VVT (variable valve timing) system on your vehicle. All of these possibilities, and quite a few others, have to be evaluated a mechanic. To have this checked for you, a qualified professional from YourMechanic can come to your home or office to diagnose the code and proceed with proper repairs.

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