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P0420 Diagnostic Trouble Code Discussion for October 2005

Catalyst Efficiency Below Normal (Bank 1)


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Trouble Ticket Help Requests for DTC P0420
Help Request Posted
2000 Honda Civic LX 1.6L MIL Lamp on VIN: 1HGEJ6677Y
P0420: Catalyst Efficiency Below Threshold (Bank 1). see above description
October 04, 2005
1998 Dodge Intrepid 2.7L Cuts out, Misfire, MIL Lamp on VIN: 2B3HD46R7W
P0420: Catalyst Efficiency Below Normal (Bank 1). Hi Group. I have a 98 intrepid thats repeatedly coming in on the hook. it dies at highway speeds, if allowed to cool for 10 or 15 min. it restarts. we have replaced the crank sensor three times, the last time we also replaced the pigtail due to a broken clip. ...
October 17, 2005
1997 Geo Metro 1.0L MIL Lamp on VIN: 2C1MR2260V
P0420: Catalyst System Low Efficiency (Bank 1). po420 cat eff. have 1.27v on scanner back probe pcm had 4.35v at yellow wire (02 sense) if pull terminal out of pcm volts comming from pcm. are there any flashes or what direction need to go? thanks for any help duane
October 20, 2005
2001 Honda CR-V LX 2.0L Surge, MIL Lamp on VIN: JHLRD28471
P0420: Catalyst Efficiency Below Threshold (Bank 1). ... today with mil on and customer says that once in a while it will shake and run rough. Had a P0420 converter deterioration code. First test for code is to clear codes and hold rpm @ 3000 until fans come on. After about 30 sec...
October 25, 2005
2000 Volkswagen Passat GLS 2.8L MIL Lamp on VIN: WVWMD23B0Y
... light on. I pulled the codes and it had a p0441 which is for the evap. canister purge flow. I did some checks and replaced the evap canister purge reg. valve, cleared the codes & sent it out. A week later car comes back with a check engine light. I pul...
October 28, 2005
2000 Honda Civic LX 1.6L MIL Lamp on VIN: 1HGEJ6677Y
P0420: Catalyst Efficiency Below Threshold (Bank 1). see above description
October 04, 2005
1998 Dodge Intrepid 2.7L Cuts out, Misfire, MIL Lamp on VIN: 2B3HD46R7W
P0420: Catalyst Efficiency Below Normal (Bank 1). Hi Group. I have a 98 intrepid thats repeatedly coming in on the hook. it dies at highway speeds, if allowed to cool for 10 or 15 min. it restarts. we have replaced the crank sensor three times, the last time we also replaced the pigtail due to a broken clip. ...
October 17, 2005
1997 Geo Metro 1.0L MIL Lamp on VIN: 2C1MR2260V
P0420: Catalyst System Low Efficiency (Bank 1). po420 cat eff. have 1.27v on scanner back probe pcm had 4.35v at yellow wire (02 sense) if pull terminal out of pcm volts comming from pcm. are there any flashes or what direction need to go? thanks for any help duane
October 20, 2005
2001 Honda CR-V LX 2.0L Surge, MIL Lamp on VIN: JHLRD28471
P0420: Catalyst Efficiency Below Threshold (Bank 1). ... today with mil on and customer says that once in a while it will shake and run rough. Had a P0420 converter deterioration code. First test for code is to clear codes and hold rpm @ 3000 until fans come on. After about 30 sec...
October 25, 2005
2000 Volkswagen Passat GLS 2.8L MIL Lamp on VIN: WVWMD23B0Y
... light on. I pulled the codes and it had a p0441 which is for the evap. canister purge flow. I did some checks and replaced the evap canister purge reg. valve, cleared the codes & sent it out. A week later car comes back with a check engine light. I pul...
October 28, 2005