A PO303 is a cylinder 3 misfire. It is most likely the cause of the PO316. The 316 just means that the PCM senses a misfire at start up (within the first 1000 revolutions of the engine). You need to check cylinder 3 to make sure the spark plug is good, the coil is good, and it is getting fuel.
Check it out and let me know what you find.
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Saturday, May 24th, 2014 AT 6:36 PM