× 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 November 2010

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 Nissan Sentra GXE 1.8L Excessive Emissions, Poor Idle Quality, Poor Fuel Economy, MIL Lamp on VIN: 3N1CB51D5Y
P0420: Catalyst Efficiency Below Normal. This converter and manifold uses packing and rings. Need to know if the flat metal gasket is also supposed to be used as well or just the round seals and rings. The after-market only knows of the flat metal one. I'm sure someone has experience with this unique...
November 02, 2010
2005 Ford F-350 Super Duty XL 5.4L No power VIN: 1FDWF36515
P0420: Bank 1 cat. Efficiency low limmt. Engine was replace in the ford dealer two month ago. No power going up hill. Rpm can not go up more then 3000 rpm when it park and race the idle.
November 04, 2010
2004 Buick Rainier CXL 5.3L MIL Lamp on VIN: 5GAET13P54
P0420: Catalyst System Low Efficiency. The vehicle has had a recuring p0420 code and now has a pending p0174 lean condition b2. I have checked the fuel pressure and volume , pressure under heavy accel. Checked the regulator, smoked the intake all ok. I checked and cleaned the maf, but was ok. The f...
November 16, 2010
2003 Chevrolet S10 LS 2.2L Surge, Cuts out, MIL Lamp on VIN: 1GCCS19H93
P0420: Catalyst System Low Efficiency. Hello everyone i have driven this car and intermittanely cuts out so fast as if it shuts down and back i cant even freeze frame on the scanner or monitor the reading anyone have this problem
November 20, 2010
2005 Nissan Pathfinder LE 4.0L MIL Lamp on, Down on power VIN: 5N1AR18W25
P0420: Catalyst Efficiency Below Normal (Bank 1). ... this Nissan is making us look bad. We have been taking care of cars for these folks for as long as we have been in business and really want to get this one fixed. We have had a few driveablity related issues recently. Cam sensor code and correction then sh...
November 23, 2010