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P0420 Diagnostic Trouble Code Discussion for March 2005

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2006 Nissan Maxima 3.0L MIL Lamp on VIN: JN1CA312DX
P0420: Catalyst Efficiency Below Normal (Bank 1). Hi everyone, This car came to us from our local dealer.Customer states that they had put all New o2 sensors into vehical.Customer says they had A ck engine light.They drove the car for a couple of days and light came on.This is where I got involved.I put my s...
March 01, 2005
1998 Honda Civic EX 1.6L Excessive Emissions VIN: 1HGEJ8248W
P0420: Catalyst Efficiency Below Threshold (Bank 1). This is a CAP (customer assistance program, State of CA) vehicle). The state is paying for the first $500. of repair, they will pay for part of the Honda new Catalytic Converter. But they fell the Nox coming into the converter is to high. Does any one out ther...
March 08, 2005
1997 Chevrolet Blazer 4.3L Hesitation, Misfire, MIL Lamp on VIN: 1GNDT13W0V
P0420: Catalyst System Low Efficiency (Bank 1). Customer brought vehicle to us with a complaint of no power. Vehicle boggs down under load. checked for codes and found po100, po300, and po420. checked MAF sensor operation and found B+, referance and activity to be ok. checked fuel pressure and found that to...
March 11, 2005
1997 Chevrolet Blazer 4.3L Hesitation, Misfire, MIL Lamp on VIN: 1GNDT13W0V
P0420: Catalyst System Low Efficiency (Bank 1). Customer brought vehicle to us with a complaint of no power. Vehicle boggs down under load. checked for codes and found po100, po300, and po420. checked MAF sensor operation and found B+, referance and activity to be ok. checked fuel pressure and found that to...
March 23, 2005