why is my check engine light on? on 2008 Pontiac G6

code p4020, dealership says its one of the catalytic converters, how do I know which one it is. And what is the cost for repair? It just crossed 100,000 K miles, is it worth repairing?

by in Houston, TX on July 11, 2014
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1 answer
ANSWER by , July 11, 2014
Did you PAY for the diagnosis? IF so the dealer should tell you.