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P0420 Diagnostic Trouble Code Discussion for March 2008

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
1997 BMW 318i 1.9L MIL Lamp on VIN: WBACC9320V
P0420: Cat. converter efficiency. ... & failed emissions.Pulled code P0420. Inspected cat and had chunks. Replaced with Catco universal converter. Cleared codes. 2 weeks passed check engine lite on again but they did pass emissions. Lab scoped 02s. Front looked great. Rear took a long time...
March 10, 2008
2001 Volvo V70 2.4L MIL Lamp on VIN: YV1SW61R31
P0420: Catalyst below efficiency. ... belongs to a friend. He is trying to pass the emission test and it won't set readiness for EVAP and catalyst. If he drives it long enough the P0420 code comes on. I tested the oxygen sensor outputs with 3 different scanners because the reading were odd. Th...
March 10, 2008
1996 Subaru Legacy L 2.2L MIL Lamp on VIN: 4S3BK4358T
P0420: Catalyst Efficiency Below Normal (Bank 1). hi subaru guys this car has the two codes , po130 ( 02 )and po420 ( cat inefficiency ) the 02 will go rich to lean just fine , and the 02 heater monitor has run to completion . the 02 monitor has not. the 02 has a definite saw tooth pattern , indicating a mis...
March 12, 2008
2001 Toyota Sienna LE 3.0L MIL Lamp on VIN: 4TZF13C61U
P0420: Catalyst Efficiency Below Normal (Bank 1). ... readiness monitor for cat. does not seem to run, but it does set a pending P0420
March 18, 2008
2000 Isuzu Trooper LS 3.5L Surge, Stall, MIL Lamp on VIN: JACDS58XOY
P0420: Catalyst Efficiency Below Normal (Bank 1). Hi, all. Customer normally uses vehicle for close local driving, within 25 miles, and has not been a problem. Recently her husband has to go to Houston weekly for cancer treatment, and it is on these 150 mile one way trips that it acts up, running at least a c...
March 19, 2008
2002 Honda CR-V EX 2.4L MIL Lamp on VIN: JHLRD788X2
P0420: Catalyst Efficiency Below Threshold (Bank 1). ... December with a p0420 stored and the light on. We cleared codes and drove the vehicle twice before the light came back on with same code. Upon monitoring the O2 sensors we noticed that the rear O2 (HO2S S2) was switching above and below the .500 threshold ...
March 24, 2008
2000 Isuzu Trooper LS 3.5L Surge, Stall, MIL Lamp on VIN: JACDS58XOY
P0420: Catalyst Efficiency Below Normal (Bank 1). Hi, all. Customer normally uses vehicle for close local driving, within 25 miles, and has not been a problem. Recently her husband has to go to Houston weekly for cancer treatment, and it is on these 150 mile one way trips that it acts up, running at least a c...
March 24, 2008
2001 Honda CR-V LX 2.0L Excessive Emissions, Surge VIN: JHLRD17471
P0420: Catalyst Efficiency Below Threshold (Bank 1). Upon cold start-up the engine idles up to 2800 rpm, then drops to 2200, then cycles continuously from the 2800 to 2200 until some heat starts to register @ the guage. The car must sit all night for these symptoms to occur. It won't exhibet these symptoms if yo...
March 25, 2008
2000 Toyota Avalon XL 3.0L MIL Lamp on VIN: 4T1BF28B9Y
P0420: Catalyst Efficiency Below Normal (Bank 1). ... inspection because of a p0420. my problem is, i don't know which cat to replace. this has 3 cats; one small one for each bank, and a larger one in the center pipe. it has an air fuel sensor in front of each front cat, and an o2 sensor behind the rear cat. ...
March 31, 2008
1997 BMW 318i 1.9L MIL Lamp on VIN: WBACC9320V
P0420: Cat. converter efficiency. ... & failed emissions.Pulled code P0420. Inspected cat and had chunks. Replaced with Catco universal converter. Cleared codes. 2 weeks passed check engine lite on again but they did pass emissions. Lab scoped 02s. Front looked great. Rear took a long time...
March 10, 2008
2001 Volvo V70 2.4L MIL Lamp on VIN: YV1SW61R31
P0420: Catalyst below efficiency. ... belongs to a friend. He is trying to pass the emission test and it won't set readiness for EVAP and catalyst. If he drives it long enough the P0420 code comes on. I tested the oxygen sensor outputs with 3 different scanners because the reading were odd. Th...
March 10, 2008
1996 Subaru Legacy L 2.2L MIL Lamp on VIN: 4S3BK4358T
P0420: Catalyst Efficiency Below Normal (Bank 1). hi subaru guys this car has the two codes , po130 ( 02 )and po420 ( cat inefficiency ) the 02 will go rich to lean just fine , and the 02 heater monitor has run to completion . the 02 monitor has not. the 02 has a definite saw tooth pattern , indicating a mis...
March 12, 2008
2001 Toyota Sienna LE 3.0L MIL Lamp on VIN: 4TZF13C61U
P0420: Catalyst Efficiency Below Normal (Bank 1). ... readiness monitor for cat. does not seem to run, but it does set a pending P0420
March 18, 2008
2000 Isuzu Trooper LS 3.5L Surge, Stall, MIL Lamp on VIN: JACDS58XOY
P0420: Catalyst Efficiency Below Normal (Bank 1). Hi, all. Customer normally uses vehicle for close local driving, within 25 miles, and has not been a problem. Recently her husband has to go to Houston weekly for cancer treatment, and it is on these 150 mile one way trips that it acts up, running at least a c...
March 19, 2008
2002 Honda CR-V EX 2.4L MIL Lamp on VIN: JHLRD788X2
P0420: Catalyst Efficiency Below Threshold (Bank 1). ... December with a p0420 stored and the light on. We cleared codes and drove the vehicle twice before the light came back on with same code. Upon monitoring the O2 sensors we noticed that the rear O2 (HO2S S2) was switching above and below the .500 threshold ...
March 24, 2008
2000 Isuzu Trooper LS 3.5L Surge, Stall, MIL Lamp on VIN: JACDS58XOY
P0420: Catalyst Efficiency Below Normal (Bank 1). Hi, all. Customer normally uses vehicle for close local driving, within 25 miles, and has not been a problem. Recently her husband has to go to Houston weekly for cancer treatment, and it is on these 150 mile one way trips that it acts up, running at least a c...
March 24, 2008
2001 Honda CR-V LX 2.0L Excessive Emissions, Surge VIN: JHLRD17471
P0420: Catalyst Efficiency Below Threshold (Bank 1). Upon cold start-up the engine idles up to 2800 rpm, then drops to 2200, then cycles continuously from the 2800 to 2200 until some heat starts to register @ the guage. The car must sit all night for these symptoms to occur. It won't exhibet these symptoms if yo...
March 25, 2008
2000 Toyota Avalon XL 3.0L MIL Lamp on VIN: 4T1BF28B9Y
P0420: Catalyst Efficiency Below Normal (Bank 1). ... inspection because of a p0420. my problem is, i don't know which cat to replace. this has 3 cats; one small one for each bank, and a larger one in the center pipe. it has an air fuel sensor in front of each front cat, and an o2 sensor behind the rear cat. ...
March 31, 2008