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P0420 Diagnostic Trouble Code Discussion for December 2005

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2001 Subaru Outback 2.5L Hesitation, MIL Lamp on VIN: 4S3BH66501
P0420: Catalyst Efficiency Below Normal (Bank 1). ... prob. p0420 in comp ...not too hard figure out ...the air fuel ratio sensor reading a fixed 1.5 volts i have no info what this should read on scan data my vantage says scan data should used ..butt with no figures need imput on this sensor, please help.
December 01, 2005
1999 Toyota 4Runner SR5 3.4L MIL Lamp on VIN: JT3GN86R3X
P0420: Catalyst Efficiency Below Normal (Bank 1). ... light on . Checked codes p0240 inefficent cat converter.The snap shot is as follows, this is with a MasterTech P0420 Calc load 31% engine speed 2268 coolant temp 201.2 f intake air 62.6 f ctp sw off vehical speed 68 mph short f t 1 1,5% ***long ft #1 17.9 ...
December 20, 2005
1997 Mazda 626 LX 2.5L Hesitation, Misfire, Poor Fuel Economy, MIL Lamp on VIN: JKI569HYT9
P0420: Catalyst Efficiency Below Normal (Bank 1). hello people, will some one help me with this ()*&^%$ box, see codes . i`m done throwing parts at it, good wind all 6 cyls, i will buy this car from the customer and personally junk it, this will be a good thing, last resort.has any one worked with these c...
December 21, 2005
1999 Toyota 4Runner SR5 3.4L MIL Lamp on VIN: JT3GN86R3X
P0420: Catalyst Efficiency Below Normal (Bank 1). ... light on . Checked codes p0240 inefficent cat converter.The snap shot is as follows, this is with a MasterTech P0420 Calc load 31% engine speed 2268 coolant temp 201.2 f intake air 62.6 f ctp sw off vehical speed 68 mph short f t 1 1,5% ***long ft #1 17.9 ...
December 22, 2005
1997 Kia Sephia GS 1.8L MIL Lamp on VIN: KNAFA1250V
P0420: Catalyst Efficiency Below Normal (Bank 1). Runs good hot and cold. Code po420(cat efficiency below threshold- bank 1) came back after cleared. Alldata said rear 02 or converter.Temp 195 deg.-both 02's scan ok.Front .2 to .8 on cruise and rear .3 to .7. I was thinking of switching the o2's if there the ...
December 31, 2005