P0420 Low Cat Efficiency Code Bypass

[rvseverson]

I don’t live in an emissions testing state so faking the computer is a nonissue for me. My 2015 Equinox has 225k miles. I just want to shut the check engine light off. I tried the #2 O2 sensor spacer. It worked for a month then the code came back. Now I’m trying the resistor/capacitor (1meg & 4.7uf) on the signal wire input. Anyone have any experience with this?

 

[PoManNox]

I never heard of the resistor thing. I don't see how that would work. If one spacer / antifouler doesn't work long term, I'd try stacking 2-3 of them. I'm about to struggle with the same thing for my 2016 Malibu 2.5L and it's only got ~100K miles on it. Living in the PR of NY, I can't even order a non CARB catalytic converter to my address. A Carb compliant unit is ~$1500.

 

[rvseverson]

I never heard of the resistor thing. I don't see how that would work. If one spacer / antifouler doesn't work long term, I'd try stacking 2-3 of them. I'm about to struggle with the same thing for my 2016 Malibu 2.5L and it's only got ~100K miles on it. Living in the PR of NY, I can't even order a non CARB catalytic converter to my address. A Carb compliant unit is ~$1500.

Yeah I might try stacking the spacers.

 

[PoManNox]

Yeah I might try stacking the spacers.

It's worth a shot. Keep us posted on it if you can please. The good thing is you can live with the MIL lit. ~11yrs/old with ~225K, that's not a bad option. Just gotta read the codes every so often to make sure no others snuck in. For me, my vehicles won't pass my yearly state inspection with the MIL lit. Things can get out of hand real quick.

 

[Jnissen]

Stacking 2-3 anti foules will usually do it. I have a 2011 Honda I’m just trying to get through another month or two. Bee. Working well so far.

 

[scan2]

I never heard of the resistor thing. I don't see how that would work. If one spacer / antifouler doesn't work long term, I'd try stacking 2-3 of them. I'm about to struggle with the same thing for my 2016 Malibu 2.5L and it's only got ~100K miles on it. Living in the PR of NY, I can't even order a non CARB catalytic converter to my address. A Carb compliant unit is ~$1500.

Maybe try ebay for the federal cat. I don't think they care about the address.. but I have never tried

 

[Jnissen]

Electrical engineer here. The Resistor cap arrangement is a low pass filter. It essentially rounds off the peaks and averages spikes out. Doubtful it will help much.

 

[rvseverson]

I don’t live in an emissions testing state so faking the computer is a nonissue for me. My 2015 Equinox has 225k miles. I just want to shut the check engine light off. I tried the #2 O2 sensor spacer. It worked for a month then the code came back. Now I’m trying the resistor/capacitor (1meg & 4.7uf) on the signal wire input. Anyone have any experience with this?

It didn’t make any difference. Still see the P0420 code. Took it off. Going to try the 90 degree adapter, for the O2 Sensor, that has a mini cat built into the end of it.