× Auto Repair Pros Member Benefits TechHelp Knowledge Base Forums Resources My iATN Marketplace Chat Pricing About Us Join Industry Sponsors Video Members Only Repair Shops Auto Pro Careers Auto Pro Reviews
Join Now
International Automotive Technicians Network

P0420 Diagnostic Trouble Code Discussion for June 2005

Catalyst Efficiency Below Normal (Bank 1)


Note: This is a professional automotive technician's resource.
Vehicle Owners: If you are seeking an automotive repair professional to service your vehicle, visit the iATN Repair Shop Finder.

Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2000 Honda Odyssey EX 3.5L MIL Lamp on VIN: 2HKRL1868Y
P0420: Catalyst Efficiency Below Threshold (Bank 1). po420 cat below efficecy
June 13, 2005
2001 Toyota Camry CE 2.2L MIL Lamp on VIN: 4T1BG22KX1
P0420: Catalyst Efficiency Below Normal (Bank 1). ... This Camry was brought to us for the check engine light being on. Another shop had performed an injector service on this car and 2 days later the light came on. Had code p0420, catalyst efficiency low. Did check as described in Alldata and no problem was f...
June 13, 2005
2001 Buick Regal LS 3.8L MIL Lamp on VIN: 2G4WB55K41
P0420: Catalyst System Low Efficiency (Bank 1). any ideas?? both o2's appear to be switching from rich to lean .1-.8 volts.
June 17, 2005
2001 Toyota Camry LE 2.2L MIL Lamp on VIN: JT2BG22K01
P0420: Catalyst Efficiency Below Normal (Bank 1). ... headgasket on this camry and about two days later car came back with mil on code p0420 cat below threshold bank1.First thing we did was replaced the converter(rear) no change second replaced front converter no change then we replaced front air fuel sensor ...
June 27, 2005