P0 420 code and oxygen scanner reference

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Richard Handwork

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The had three codes normal saved and permanent . If I cleared normal code it would run 15 miles. If I cleared normal, saved it would run 110 miles. I found four 20 amp fuses with no power.
I disconnected both wires battery cables. Tied together with wire ties. I let sit all night. and reconnected. It turned power to the fuses. This restored power to the oxygen sensors, I had installed two new front sensors. They worked but not correctly. I then installed a new canister purge valve this got the oxygen sensors working properly l as I got a new scanner with graphing capabilities.and checked. It also dropped the permanent code. I'm going to drive it for a while to check if the code stays off. Has anyone else fixed this code with a canister purge valve.
 

NavyStore

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Never seen this code, but now I'm wondering how often people are having these electrical system glitches. Let us know how your repair works!
 

gfe kj

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The had three codes normal saved and permanent . If I cleared normal code it would run 15 miles. If I cleared normal, saved it would run 110 miles. I found four 20 amp fuses with no power.
I disconnected both wires battery cables. Tied together with wire ties. I let sit all night. and reconnected. It turned power to the fuses. This restored power to the oxygen sensors, I had installed two new front sensors. They worked but not correctly. I then installed a new canister purge valve this got the oxygen sensors working properly l as I got a new scanner with graphing capabilities.and checked. It also dropped the permanent code. I'm going to drive it for a while to check if the code stays off. Has anyone else fixed this code with a canister purge valve.
I have been getting this code for a couple of years. I found out non MOPAR parts don't work well with the MOPAR PCM. I replaced them with Mopar sensors and most of my codes went away. The P 0420 is generic and now I'm told I need a new Cat converter. I will try to "clean" it before making that step.
 

Richard Handwork

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I have been getting this code for a couple of years. I found out non MOPAR parts don't work well with the MOPAR PCM. I replaced them with Mopar sensors and most of my codes went away. The P 0420 is generic and now I'm told I need a new Cat converter. I will try to "clean" it before making that step.
I installed a new canister purge valve and it cured my code P 0420 my fuel air mixture was rich.
 

Richard Handwork

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I have been getting this code for a couple of years. I found out non MOPAR parts don't work well with the MOPAR PCM. I replaced them with Mopar sensors and most of my codes went away. The P 0420 is generic and now I'm told I need a new Cat converter. I will try to "clean" it before making that step.
I have over twice the miles I used to be able to go without setting the code.The reason I tied the battery cables is I installed a rebuilt TIPM this drains a capacitor wich allows the cpu to accept the unit. This allowed the fuses to work for power to the oxygen sensors.
 

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