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Q: Engine running rough and won't accelerate

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The car will start fine but won't move off with normal accelerator application. I have replaced the throttle position sensor and no change. If you put the pedal hard to the floor it will take off and seems to run ok once above 2500 - 3000RPM.The engine warning light is on and indicates P0031 and P0037.

I have replaced the O2 sensors either side of the catalytic convertor with no change. I have installed a new air line from the filter to the turbo charger body.

This vehicle is driving me nuts. Any ideas?

My car has 109000 miles.
My car has an automatic transmission.

Hi, thanks for writing in. The camshaft and crankshaft position sensors are a possible cause of the symptoms you described. Having these sensors tested professionally using the manufacturer’s recommended procedure would by my best recommendation. If one of these two sensors fails the test, it is a good idea to go ahead and change them both due to the fact that they work together to send a signal to the vehicle’s PCM and they have likely been on the vehicle for the same amount of time. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

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