Do the tune-up first before replacing your converter. This is because if your engine isn't tuned up the un-burnt fuel can ruin your bran new catalytic converter.
Those codes (p302, p0303, etc) are all mis-fire codes. Meaning a cylinder isn't firing properly (must likely caused by a foul spark plug or wire)
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Thursday, February 18th, 2010 AT 6:16 PM