Well Byant, A code reader would be fine. They are fairly in expensive.
If it is a Cam Sensor, your car has two of them and it's best to replace them in pairs. Also, if it is a electrical sensor causing this, don't get the parts from your local auto parts store. After Market electrical parts never work right. Get the sensors from the dealer. They are around 90 bucks each and as far as labor to replace them, you are looking at around 1 1/2 hours labor. Just remember if you do have cam sensors done, make sure they do not clean the throttle chamber. If they do, they could damage it if they don't use the right cleaners and it will require a idle relearn after cleaned.
After you get the code, if you would like to return back for more help on this, please just return back and let me know the code. If it is a Cam Sensor, then you know what needs to be done.
If you have any more questions on this, please feel free to ask.
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