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P0420 Diagnostic Trouble Code Discussion for October 2009

Catalyst Efficiency Below Normal (Bank 1)

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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2004 Dodge Grand Caravan SXT 3.8L MIL Lamp on, P0420 VIN: 2D4GP44L04
P0420: Catalyst Efficiency Below Normal (Bank 1). ... code p0420. the catalyst has been replaced numerous times. both o2 sensors have been replaced recently.the last time the catalyst was replaced was two years ago. the weird thing is that when i check the freeze frame for the code p0420 the coolant temp was ...
October 06, 2009
2005 Nissan Titan LE 5.6L MIL Lamp on VIN: 1N6AA06AX5
P0420: Three-Way Catalyst Malfunction (Bank 1). Good Day all ! Have these two cat codes ( PO420 and PO430 for low effiency on both banks ) and no other codes and truck runs very good - no problems. I looked for TSB's - none found and I looked in the achieves but nothing found there also. Only has 67,000 mil...
October 12, 2009
2001 Subaru Forester L 2.5L MIL Lamp on VIN: JF1SF65651
P0420: Catalyst Efficiency Below Normal (Bank 1). ... this work was done. All 3 times with a check engine light on with a P0420. We replaced the gasket between the engine pipe and the convertor the first time it was back because there appeared to be a slight leak there. Second time we shut the light off and l...
October 23, 2009
2006 Nissan Altima SL 2.5L Poor Idle Quality, Surge VIN: 1N4AL11D06
P0420: Catalyst Efficiency Below Normal (Bank 1). Hey guys! I have been working with this car for about 2 weeks now. It cam into my shop from another shop down the road I replaced the head gasket because of antifreeze in the cylinders. The timming marks on the cams line up with the marks on the chain but on t...
October 27, 2009
1998 Chevrolet Malibu 2.4L Poor Idle Quality, Hesitation, Cuts out, Misfire, MIL Lamp on VIN: 1G1ND52T0W
P0420: Catalyst System Low Efficiency (Bank 1). This vehicle came in running very poorly. I have found various problems with several systems as you can tell by the repair history.(the exhaust cam was even off a tooth due the the tensioner malfunction) Now I have isolated a misfire and bucking going up hill ...
October 28, 2009
2006 Ford E-250 4.6L Misfire, MIL Lamp on VIN: 1FTNE24N86
P0420: insufficient catalyst efficiency bank 1. Got one that I have some suspicions about, but would like some input. I had the van in two weeks ago, it had coded for B1S1 O2 fault, testing confirmed that it was indeed faulty, and I replaced it. Came back in today with an insufficient catalyst code on the ...
October 28, 2009
1999 Ford Ranger XLT 4.0L Poor Idle Quality, MIL Lamp on VIN: 1FTZR15X9X
P0420: catalyst system efficency below threshold bank 1. vehilce is a california emmision vehicle per vin. no egr, dpfe, or egr solenoid found in system.also has: p1715 mechanical failure of solenoid a detected. p1717 mechanical failure of solenoid d detected.
October 30, 2009
2001 Oldsmobile Alero GL 2.4L Poor Idle Quality VIN: 1G3NL52T31
P0420: Catalyst System Low Efficiency. This car came in for a leaking fuel press. regulator. We also noticed that idle was high so customer said to go ahead and fix. Have replaced IAC motor, new motor actually made idle increase even more. Check tps with scope, normal. Checked for vaccume leak, non...
October 30, 2009