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P0420 Diagnostic Trouble Code Discussion for June 2006

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2003 Toyota Celica GT 1.8L MIL Lamp on VIN: JTDDR32T63
P0420: Catalyst Efficiency Below Normal (Bank 1). Catalytic converter assembly was replaced due to code PO420.The vehicle was brought to us with the mil on again. The same code is present. The customer was unable to provide any info as to how the cat was tested and condemned. There is approximately 900 miles ...
June 05, 2006
2001 Toyota Tacoma Pre Runner 3.4L MIL Lamp on VIN: 5TEGN92N71
P0420: Catalyst Efficiency Below Normal (Bank 1). Here's a hair puller for you. This truck has a salvage title and no longer is covered by mfr's 8/80 warranty. It keeps setting a CAT code intermittently. Sometimes the client can take it and it sets on his way home after 2 miles. Other times it takes 6 weeks a...
June 12, 2006
2001 Toyota Tacoma Pre Runner 3.4L MIL Lamp on VIN: 5TEGN92N71
P0420: Catalyst Efficiency Below Normal (Bank 1). Here's a hair puller for you. This truck has a salvage title and no longer is covered by mfr's 8/80 warranty. It keeps setting a CAT code intermittently. Sometimes the client can take it and it sets on his way home after 2 miles. Other times it takes 6 weeks a...
June 13, 2006
2002 GMC Sierra 1500 SL 4.8L MIL Lamp on VIN: 2GTEK19V12
P0420: Catalyst System Low Efficiency (Bank 1). Have cat code Bank one - PO420 - efficiency below threshold. Also has a pending code for the same code. This code appeared before (within one year), was cleared and not returned until today. Question is freeze frame showed code setting at 588 RPM, 0% throttle,...
June 16, 2006
2003 Toyota Celica GT 1.8L MIL Lamp on VIN: JTDDR32T63
P0420: Catalyst Efficiency Below Normal (Bank 1). Catalytic converter assembly was replaced due to code PO420.The vehicle was brought to us with the mil on again. The same code is present. The customer was unable to provide any info as to how the cat was tested and condemned. There is approximately 900 miles ...
June 05, 2006
2001 Toyota Tacoma Pre Runner 3.4L MIL Lamp on VIN: 5TEGN92N71
P0420: Catalyst Efficiency Below Normal (Bank 1). Here's a hair puller for you. This truck has a salvage title and no longer is covered by mfr's 8/80 warranty. It keeps setting a CAT code intermittently. Sometimes the client can take it and it sets on his way home after 2 miles. Other times it takes 6 weeks a...
June 12, 2006
2001 Toyota Tacoma Pre Runner 3.4L MIL Lamp on VIN: 5TEGN92N71
P0420: Catalyst Efficiency Below Normal (Bank 1). Here's a hair puller for you. This truck has a salvage title and no longer is covered by mfr's 8/80 warranty. It keeps setting a CAT code intermittently. Sometimes the client can take it and it sets on his way home after 2 miles. Other times it takes 6 weeks a...
June 13, 2006
2002 GMC Sierra 1500 SL 4.8L MIL Lamp on VIN: 2GTEK19V12
P0420: Catalyst System Low Efficiency (Bank 1). Have cat code Bank one - PO420 - efficiency below threshold. Also has a pending code for the same code. This code appeared before (within one year), was cleared and not returned until today. Question is freeze frame showed code setting at 588 RPM, 0% throttle,...
June 16, 2006