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Home >> Chevrolet >> 2006 >> HHR LS, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 2.2L - DTC P0136 To P0446 >> DTC P0420 >> Repair Procedures
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Repair Procedures

IMPORTANT: A new converter with less than 100 miles on it may set P0420 due to out-gassing of the internal matting. Operating the vehicle at highway speeds for approximately 1 hour may correct the condition.
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