P0420 what can it be?
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P0420 what can it be?
The other day my check engine light came on with the p0420 code, of course I want to check every problem before I chanhe the catalytic converter. I checked the o2 sensors and while the upstream sensor (bank 1 sensor 1) shows an alternating curve while driving, the downstream (bank 1 sensor 2) does not follow it like one would think. When idling sensor 2 indicates .2 volts, but when driving it shows higher numbers than sensor 1. Sensor 2 is at about .7-8 while sensor 1 is about .5. Is it possible that my sensor 2 is faulty? Help please
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Re: P0420 what can it be?
my bet is for actual cat. I never took voltage readings, so I couldn't tell you voltage range for proper ops, but could be that your cat is literally under efficiency threshold.
Pure speculation here, coupled with very quick googling for numbers.. Average cat lifespan is 100k miles. Could also mean internal damage to the honeycomb structure, allowing more un-catalyzed exhaust gases (CO and NOx) being read by the secondary sensor. No lie, couldn't find anything concrete about the substrate(s) used (other than precious metals) and if/how they can be spent.
I mean, if the 420 code isn't causing any performance issues, there are ways to make that light go away, and I have passed OBD port smog checks with that mod in place. Just look up what people with high flow cats and/or test pipes do. Cost me like $3 to do
Pure speculation here, coupled with very quick googling for numbers.. Average cat lifespan is 100k miles. Could also mean internal damage to the honeycomb structure, allowing more un-catalyzed exhaust gases (CO and NOx) being read by the secondary sensor. No lie, couldn't find anything concrete about the substrate(s) used (other than precious metals) and if/how they can be spent.
I mean, if the 420 code isn't causing any performance issues, there are ways to make that light go away, and I have passed OBD port smog checks with that mod in place. Just look up what people with high flow cats and/or test pipes do. Cost me like $3 to do
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If your losing a quart plus of oil between oil changes (or fillups when really bad) it most likely is a clogged up cat.
If your really lucky like me, your clogged up cat will shatter and you will have chunks of black plastic like rocks all though your exhaust piping.
Bang the resonator few times and listen for rattles.
If your really lucky like me, your clogged up cat will shatter and you will have chunks of black plastic like rocks all though your exhaust piping.
Bang the resonator few times and listen for rattles.
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my bet is for actual cat. I never took voltage readings, so I couldn't tell you voltage range for proper ops, but could be that your cat is literally under efficiency threshold.
Pure speculation here, coupled with very quick googling for numbers.. Average cat lifespan is 100k miles. Could also mean internal damage to the honeycomb structure, allowing more un-catalyzed exhaust gases (CO and NOx) being read by the secondary sensor. No lie, couldn't find anything concrete about the substrate(s) used (other than precious metals) and if/how they can be spent.
I mean, if the 420 code isn't causing any performance issues, there are ways to make that light go away, and I have passed OBD port smog checks with that mod in place. Just look up what people with high flow cats and/or test pipes do. Cost me like $3 to do
Pure speculation here, coupled with very quick googling for numbers.. Average cat lifespan is 100k miles. Could also mean internal damage to the honeycomb structure, allowing more un-catalyzed exhaust gases (CO and NOx) being read by the secondary sensor. No lie, couldn't find anything concrete about the substrate(s) used (other than precious metals) and if/how they can be spent.
I mean, if the 420 code isn't causing any performance issues, there are ways to make that light go away, and I have passed OBD port smog checks with that mod in place. Just look up what people with high flow cats and/or test pipes do. Cost me like $3 to do
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