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Q: Car running rough and engine races

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My car starts rough. The engine races and then white smoke comes out of the exhaust. I am not currently getting a Check Engine light or error codes, other than the code P1399.

Hi. White smoke indicates that you have a blown head gasket. The motor may have overheated, warping the head and causing coolant to leak into the cylinder. I would recommend a complete engine rebuild for this problem. I would look in the oil fill cap and look for a milky looking sludge built up in the valve cover. That will indicate coolant in oil and a blown head gasket. If you need further assistance, I recommend you have a mechanic, like one from YourMechanic, diagnose your vehicle’s smoke issue and for head gasket damage.

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