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P0420 Diagnostic Trouble Code Discussion for September 2013

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2006 Volvo S40 2.4i 2.4L Excessive Emissions VIN: YV1MS38226
P0420: Catalytic Efficiency Bank1. Vehicle came in with a code P0420 Catalytic Efficiency Bank1. looking at Long and Short term fuel trims, found LTFT -10 and STFT around -1 to -0.8 never goes lean. Upon revving engine fuel trims get better and come back closer to 0 on LTFT. Almost like an vacu...
September 16, 2013
2006 Volvo S40 2.4i 2.4L Excessive Emissions VIN: YV1MS38226
P0420: Catalytic Efficiency Bank1. Vehicle came in with a code P0420 Catalytic Efficiency Bank1. looking at Long and Short term fuel trims, found LTFT -10 and STFT around -1 to -0.8 never goes lean. Upon revving engine fuel trims get better and come back closer to 0 on LTFT. Almost like an vacu...
September 17, 2013
1997 BMW Z3 Roadster 1.9L MIL Lamp on VIN: 4USCH7322V
P0420: Catalyst efficiency. My question on this one is why do I never see 100% calculated load value? I know the fix will be to install a BMW cat. I inherited this job and the customer got involved with the manufacturer of the aftermarket cat. The manufacturers engineer insists that his ...
September 18, 2013
2009 Chevrolet Traverse LS 3.6L MIL Lamp on VIN: 1GNER13D69
... came in with p2097, p2099, p0420, p0430. I cleared codes and drove it for a day. only codes p0420 and p0430 reset. I seen a couple of service messages/tsbs for these vehicles saying check for exhaust leaks, injector problem...
September 19, 2013
2006 Volvo S40 2.4i 2.4L Excessive Emissions VIN: YV1MS38226
P0420: Catalytic Efficiency Bank1. Vehicle came in with a code P0420 Catalytic Efficiency Bank1. looking at Long and Short term fuel trims, found LTFT -10 and STFT around -1 to -0.8 never goes lean. Upon revving engine fuel trims get better and come back closer to 0 on LTFT. Almost like an vacu...
September 16, 2013
2006 Volvo S40 2.4i 2.4L Excessive Emissions VIN: YV1MS38226
P0420: Catalytic Efficiency Bank1. Vehicle came in with a code P0420 Catalytic Efficiency Bank1. looking at Long and Short term fuel trims, found LTFT -10 and STFT around -1 to -0.8 never goes lean. Upon revving engine fuel trims get better and come back closer to 0 on LTFT. Almost like an vacu...
September 17, 2013
1997 BMW Z3 Roadster 1.9L MIL Lamp on VIN: 4USCH7322V
P0420: Catalyst efficiency. My question on this one is why do I never see 100% calculated load value? I know the fix will be to install a BMW cat. I inherited this job and the customer got involved with the manufacturer of the aftermarket cat. The manufacturers engineer insists that his ...
September 18, 2013
2009 Chevrolet Traverse LS 3.6L MIL Lamp on VIN: 1GNER13D69
... came in with p2097, p2099, p0420, p0430. I cleared codes and drove it for a day. only codes p0420 and p0430 reset. I seen a couple of service messages/tsbs for these vehicles saying check for exhaust leaks, injector problem...
September 19, 2013