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P0420 Diagnostic Trouble Code Discussion for January 2006

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
1998 Toyota Camry CE 2.2L MIL Lamp on VIN: 4T1BG22K5W
P0420: Catalyst Efficiency Below Normal (Bank 1). cAR CAME IN RUNNING ROUGH WITH CHECK ENGINE LIGHT ON. HAD FRONT O2 SENSOR CODE I FORGET WHICH ONE AND PO420. I FOUND WRONG SENSOR IN FRONT OF CAT. HAD AN O2 SENSOR RATHER THAN A A/F SENSOR. REPLACED WITH A/F SENSOR AND REPLACED PLUGS AND WIRES. RESET COMPUTER....
January 05, 2006
1999 Subaru Forester L 2.5L Excessive Emissions, Poor Idle Quality, MIL Lamp on VIN: JF1SF6352X
P0420: Catalyst Efficiency Below Normal (Bank 1). ... here, this car has been to the dealership, a couple different shops and has wound up in our hands now. This Forester keeps setting P0420 cat eff. codes. It had a head gskt job done at another shop and 8 months later keeps setting this code. No other codes,...
January 06, 2006
1999 Chevrolet Astro 4.3L Poor Idle Quality, Surge, MIL Lamp on VIN: 1GCDM19WOX
P0420: Catalyst System Low Efficiency (Bank 1). ... codes only code p1870. recheck cam retard reads -60 at idle. what is causing the cam retard to go crazy.
January 11, 2006
2002 Toyota Camry SE 2.4L MIL Lamp on VIN: JTDBE32K22
P0420: Catalyst Efficiency Below Normal (Bank 1). ... #P0420. I followed the Toyota diag chart from AllData and came up with a bad catalytic converter diagnosis but I'm left with some questions since I am not that familiar with Toyota. First, the readings on the scan tool for what I think is post cat O2 rea...
January 11, 2006
2001 Chevrolet Venture LS 3.4L Excessive Emissions, MIL Lamp on VIN: 1GNDX03EX1
P0420: Catalyst System Low Efficiency. ... frame data always shows between 600-700rpm. This van originaly had a convertor replaced by another tech about 1 year ago. I got it a couple of weeks ago because of the P0420 DTC. Checked it out and found a dirty MAF and convertor oxygen storage to be low. ...
January 31, 2006
1998 Toyota Camry CE 2.2L MIL Lamp on VIN: 4T1BG22K5W
P0420: Catalyst Efficiency Below Normal (Bank 1). cAR CAME IN RUNNING ROUGH WITH CHECK ENGINE LIGHT ON. HAD FRONT O2 SENSOR CODE I FORGET WHICH ONE AND PO420. I FOUND WRONG SENSOR IN FRONT OF CAT. HAD AN O2 SENSOR RATHER THAN A A/F SENSOR. REPLACED WITH A/F SENSOR AND REPLACED PLUGS AND WIRES. RESET COMPUTER....
January 05, 2006
1999 Subaru Forester L 2.5L Excessive Emissions, Poor Idle Quality, MIL Lamp on VIN: JF1SF6352X
P0420: Catalyst Efficiency Below Normal (Bank 1). ... here, this car has been to the dealership, a couple different shops and has wound up in our hands now. This Forester keeps setting P0420 cat eff. codes. It had a head gskt job done at another shop and 8 months later keeps setting this code. No other codes,...
January 06, 2006
1999 Chevrolet Astro 4.3L Poor Idle Quality, Surge, MIL Lamp on VIN: 1GCDM19WOX
P0420: Catalyst System Low Efficiency (Bank 1). ... codes only code p1870. recheck cam retard reads -60 at idle. what is causing the cam retard to go crazy.
January 11, 2006
2002 Toyota Camry SE 2.4L MIL Lamp on VIN: JTDBE32K22
P0420: Catalyst Efficiency Below Normal (Bank 1). ... #P0420. I followed the Toyota diag chart from AllData and came up with a bad catalytic converter diagnosis but I'm left with some questions since I am not that familiar with Toyota. First, the readings on the scan tool for what I think is post cat O2 rea...
January 11, 2006
2001 Chevrolet Venture LS 3.4L Excessive Emissions, MIL Lamp on VIN: 1GNDX03EX1
P0420: Catalyst System Low Efficiency. ... frame data always shows between 600-700rpm. This van originaly had a convertor replaced by another tech about 1 year ago. I got it a couple of weeks ago because of the P0420 DTC. Checked it out and found a dirty MAF and convertor oxygen storage to be low. ...
January 31, 2006