BeachVette6
New member
Hi, Can a 0420 code be caused by a defective downstream O2 sensor?
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OBD Code O420 Help
- Thread starter BeachVette6
- Start date
Fivefingerdeathpunch
New member
Re: O420 Help
Could it, maybe.
But just about every single time it's still the cat converter that is no longer up to par with what the vehicle wants to see.
Could it, maybe.
But just about every single time it's still the cat converter that is no longer up to par with what the vehicle wants to see.
BeachVette6
New member
Re: O420 Help
The odd thing is I took it for the state emission test and with probe in the tail pipe all readings were way below the thresholds.The cat must be functioning correctly? The only reason it did not pass was that one monitor was not back on line as I had cleared the all the codes a couple of days before.
The odd thing is I took it for the state emission test and with probe in the tail pipe all readings were way below the thresholds.The cat must be functioning correctly? The only reason it did not pass was that one monitor was not back on line as I had cleared the all the codes a couple of days before.
BeachVette6
New member
I just looked at the print out from the smog station again and all the readings are below normal. The catalyst checks good. Any ideas?