Catalyst Codes
 

My smog is due next February, and today P0420 and P0430 popped up when the monitoring finally completed.

Last smog I had a P0430 that I successfully got rid of using a can of CRC guaranteed to pass, even though its not "for" catalytic converter monitoring.

Between then and now I had an AOS failure with tons of oil smoke that I'm sure didn't help the situation.

I've heard of success stories using Oxicat, O2 sensor spacers, and O2 sensor filters. What's worked for everyone here? I don't want to buy another set of converters. Is there an OTS tune which can trick the readiness sensors? How do people with catless headers pass?

Imho the catalytic converters clean themselves when they have been at temperature for long enough. If the catalytic converters are physically in order (nothing rattles when you knock on the housing), warm up the engine and then don't run it below 3,000 rpm for as long as possible, go uphill. You can support this with an additive in the tank, i'm not a fan of that. Afterwards, you can also do an oil- and oilfilter change if it's due anyway.

Ok I actually happened to commute up a extended uphill road today. Kept it at 4000+ rpm and saw a healthy amount of smoke out the back. Hopefully that was the cats getting hot and not just my spark plug tubes lol.

But the AOS is repaired and we are only talking about residual oil in the system? What is your oil consumption?

But did you clean the air intake system? A failing AOS dumps lots of stuff into the air intake and all over the throttle body. Plus are all the hoses solid and secure. It is an old car and stuff ages.

I have 0 oil consumption for the 3 years I’ve had the car aside from spark plug tube leak. However that’s never made a quantifiable change in oil level including now.

Also no to cleaning out the intake. I think all the residual oil is burned off already. It’s been a month or more since the AOS was swapped out and for the few days following it I saw some smoke out of the tailpipe but nothing after that unless there’s a pool of it that’s remaining until higher vacuum force from high RPMs suck it in.

Italian tuneup. Few launches, pull battery cable, retest.

sounds like a typical drive to work for me! Hopefully I can burn it all off by February lol.