I have a 2002 Mazda millenia 2.5 it's showing a po303 code which is a misfire in cyl. 3 I've seen several different possible problems doing research on the net but I need a sure fire fix
It will need a Cat if you keep driving it with a miss-fire on the #3 cylinder. Probably a spark plug or plug wire. Catalytic Converters plug up - they do not trip miss-fire codes.
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