P0420 Diagnostic Trouble Code Discussion for December 2014
Catalyst Efficiency Below Normal (Bank 1)
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| Help Request | Posted | |
| 2003 Toyota Sienna CE 3.0L MIL Lamp on VIN: 4T3ZF19CX3 P0420: Catalyst Efficiency Below Normal (Bank 1). ... advance for your willingness to help/provide insight. The story - this old (240K miles) Sienna starting popping a P0420 code approx every couple of months over the last year. It's been working all these years with the original ECM (even though Toyota relea... |
December 02, 2014 | |
| 1997 Mazda Protege DX 1.5L No communication VIN: JM1BC1415V P0420: Catalyst Efficiency Below Normal (Bank 1). Hi need some assistance from the old school Mazda techs. This car came in for a failed emissions test with a code p420. I was unable to communicate with the ecu to verify the code. Now the problem is no communication with the ecu. I have power and ground at pr... |
December 03, 2014 | |
| 2005 Nissan Altima S 2.5L Poor Idle Quality, Surge, MIL Lamp on VIN: 1N4AL11D95 P0420: Catalyst Efficiency Below Normal (Bank 1). Ok this nissan has been sitting over a year. Batt was toast, and did some brake work, got it running drove for a week or so and lite came on 420 i know is the cat it's toast, the 455 was vent stuck open thats fixed new vent valve. Now the 507, tried cleaning t... |
December 03, 2014 | |
| 2004 Nissan Sentra SE-R 2.5L MIL Lamp on VIN: 3N1AB51D04 P0420: Catalyst Efficiency Below Normal. We have a 2004 sentra here that came in with a cat code and the cat definitely shows bad on scan data during a drive cycle. The issue that bugs me is that the vehicle is staying in open loop all the time even though all the data pids look normal other than the... |
December 17, 2014 | |
| 2006 Honda Pilot EX 3.5L Excessive Emissions, Poor Fuel Economy, MIL Lamp on VIN: 5FNYF28656 P0420: Catalyst Efficiency Below Threshold (Bank 1). Vehicle apppears to run fine. Using scan tool,and viewing O2 sensors Bank 1 appears lazy in switching, Practically a flat line when viewed against the bank 2 ,O2 sensor. Upon increasing RPM they come alive, the B1 sensor is still Weak , the B2 looks like a nor... |
December 19, 2014 | |
| 2004 Nissan Sentra SE-R 2.5L MIL Lamp on VIN: 3N1AB51D04 P0420: Catalyst Efficiency Below Normal. We have a 2004 sentra here that came in with a cat code and the cat definitely shows bad on scan data during a drive cycle. The issue that bugs me is that the vehicle is staying in open loop all the time even though all the data pids look normal other than the... |
December 19, 2014 |
