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Home >> Acura >> 2003 >> 3.2CL Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Performance System Self-Diagnostics >> Diagnostic Tests >> DTC P0420: Catalyst System Efficiency Below Threshold >> Notes
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DTC P0420: Catalyst System Efficiency Below Threshold: Notes

NOTE: If DTCs P0137, P0138 or P0141 are also stored, troubleshoot these codes first.
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