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Q: Engine running rough

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Engine has been running rough for a few months, engine would stop at red lights occasionally, took it in, they changed spark plugs and the gas cap, worked better for a while. About two months ago it started again, the engine would choke and sputter and die, or almost die but would recover. It would always come back on, if it died. This week the check engine came on with codes p0335 and p0456. This is our only vehicle so we are hoping to get this resolved quickly. Thanks for the help, Nick.

My car has 70000 miles.
My car has an automatic transmission.

Hi there. The P0335 OBD-II error code is set once the power train control module (PCM) fails to detect proper sensor operation from the crankshaft position sensor. This causes the Check Engine Light to be displayed on the dashboard and a fail safe mode enabled. P0456 is an OBD-II generic code that the engine control module (ECM) has detected a very small leak in the evaporative system. It’s possible that your Patriot has an issue within the EVAP system, which tends to create the symptoms you’re experiencing. To determine which component is faulty, please contact a professional mobile mechanic to come to your location and complete a car idle is rough inspection.

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