Q: Car runs rough below 40 MPH

asked by on February 18, 2016

My car runs rough when driving below 40 MPH. The emission and low tire pressure lights are on, and I am getting OBD codes P0171, P0301, and P0316.

The code P0171 means that the engine running lean, which typically stems from a few possible sources: a faulty mass air flow sensor, or clogged intake manifold gaskets or fuel filter. The codes P0301 and P0316 can mean that cylinder number one is misfiring, which could stem from the coil. I recommend that you have a mechanic, such as one from YourMechanic, come to you and run a full diagnostic on your engine misfire issue, then estimate the repairs needed to fix your Windstar.

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