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P0420 Diagnostic Trouble Code Discussion for March 2010

Catalyst Efficiency Below Normal (Bank 1)

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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2005 Toyota Corolla S 1.8L MIL Lamp on VIN: 1NXBR32E35
P0420: Catalyst Efficiency Below Normal (Bank 1). ... Toyota before I give the customer a heart attack with the estimate. Woman says the SES light has been off and on for quite some time now. Pulled codes and got a P0420. Using the Snap-On Modis, I can't seem to get a PID for the A/F sensor. Backprobing it I ...
March 02, 2010
1997 Ford F-150 XL 4.6L MIL Lamp on VIN: 1FTDF1762V
P0420: bank1 catalyst enefficiency. This is 3rd vehicle in 3 months showing a baro reading of 26.9".Whether or not that is relevent to the cat code this vehicle has ,I don't know.I am near sea level and the baro readings I normally see are around 28-29".I find it very odd that 3 differen...
March 18, 2010
1999 Dodge Caravan 3.0L Poor Idle Quality, Hesitation, Surge, Cuts out, Misfire, MIL Lamp on VIN: 2B4FP2530X
P0420: Catalyst Efficiency Below Normal (Bank 1). I have a gem here. Gut says PCM. This van has multiple codes. Has severe misfire even at steady speeds(ALMOST all the time) but occasionally will run smooth at steady cruise. It starts and idles great. Under accel will usually fall flat on its face and as you ...
March 20, 2010
2002 Toyota Tacoma DLX 3.4L MIL Lamp on VIN: 5TEHN72N02
P0420: Catalyst Efficiency Below Normal (Bank 1). hey everyone; from the info i have found the upstream sensor should be at 3.3v, if it is above that it is running lean. the only thing that i know of that can cause that and still have fuel trim in check would be maf. do those numbers seem out of line? ( in ...
March 25, 2010
2005 Ford F-250 Super Duty XLT 5.4L Poor Idle Quality, Surge, Stall, Misfire VIN: 1FTNF21515
P0420: cat. efficiency B1. The vehicle came in for no power problem. It was misfiring bad. We replaced the coils & plugs on cyl. 1,2,& 3 along with the fuel filter. (It had water in one of the plug holes & moisture in the pcm connectors.) The misfire is gone but still runs p...
March 26, 2010