[Aaronm206]

Hey all, I have a N54 with 145K on it that I just upgraded to index 12 injectors (yes I coded them). the car wont pass smog due to the P0420 and P0430 codes. Could this be due to the new injectors? Will new high flow cats pass Ca. smog? The only other engine "mod" is a charge pipe w BOV.

[lowrydr310]

Originally Posted by Aaronm206

Hey all, I have a N54 with 145K on it that I just upgraded to index 12 injectors (yes I coded them). the car wont pass smog due to the P0420 and P0430 codes. Could this be due to the new injectors? Will new high flow cats pass Ca. smog? The only other engine "mod" is a charge pipe w BOV.

You might just have bad oxygen sensors.

Injectors aren't going to trigger catalyst efficiency codes, that's likely just a coincidence.

You won't pass smog with high flow cats; they would fail visual inspection by a competent technician since there aren't any high flow cats that have the required CARB EO number/approval.

Charge pipe with BOV is also a cause for failure.

[whyzee125]

Best case your O2’s are failing, more likely your cats are failing. Unrelated to the new injectors.

[topfuel67]

I'm in CA and have dealt with smog a lot. Technically high flow cats will not pass smog if the codes engraved on them are not CA compliant IF the car was originally delivered to CA. IF your car was originally purchased out of CA and then later brought in you can get away with running high flow cats as long as they're 49 state legal. If the smog station catches the non-CA code they won't pass it either way. IF you have a non-CA car with those cats you can call the CA smog ref and they'll smog your car at a community college for the $8.25 fee. I have a 93 jeep that I went through all this with.