Jessicasdd

I have replaced the O2 sensors. That was the first thing done after getting this code. I even tried everything I read in someone else's thread about everything they did when getting the P0420 code. This code kicked after everything else was fixed. I would love to not have to replace the cat again but my mechanic said it's that last thing that hasn't been done since fixing everything else. Just afraid that if I get the same one this could happen again. But maybe the part RJ suggested will help. I need to get my HHR up on a lift so i can see under it. We got a foot and a half of snow on Monday so i can't even see under it in my driveway right now. But I do know the heat shield is either hanging or bent because you can hear it vibrating when the car is running. So maybe... just maybe. LOL

Thanks,
Jessica

Oldblue

I installed one of those O2 extenders in Oldblue, the catalytic converter clogged up anyways and I had to replace it, so it’s a gamble.

Jessicasdd

Everything is a gamble these days. LOL Look how much I put into it. The dealer keeps telling me it's a hot commodity. I've put about $4000 into with the engine replacement and everything else I've done and they offered me $1140. LOL They just gave my mom $10k for her car that was only 3 years newer. LOL I'll keep my hot commodity. I like it too much to get rid of it anyway.

fastsuv

Jessica:

A few years ago I installed a new converter on my 2006 1LT HHR 2.4L because the flex pipe broke and leaked.

I bought one from Ebay from Canada for about $120. It was not CARB certified.

It worked, did not set any codes, and passed inspection.

NY emission inspection (in Western New York at least) consists of reading the computer for codes. Pending codes will pass as long as the MIL isn't lit up on the dash. No tailpipe sniffer. I think the inspector also has to "look for the presence of a catalytic converter".

Steve

Vehicles that are 10 yrs old or more can have one readiness monitor not ready. Usually the last readiness monitor to set is the EVAP test, which sometimes takes a week or more.

fastsuv

I forgot to mention, a shop won't install a non-CARB converter in NY because they could get in a lot of trouble and lose their certification.

My daughter who lives in a different part of the state, had to replace the converter on her HHR. The mechanic shopped around for the best deal, but the part was still around $700 or so for the CARB certified one.

Steve

donbrew

https://www.dec.ny.gov/docs/air_pdf/amccchklst.pdf
https://www.walkerexhaust.com/suppor...ter-guide.html
Check the emissions label under the hood; if it says "50 states" or "CARB" you must replace it with CARB or 50 state converter. If the label says "FEDERAL" you can use any cat.
All replacement converters must be warranted for at least 5 years and mechanics have to fill out a regulatory form.

Or, look at your RPO label on the glovebox door; NT7 IS Federal, NI1 means California Lev 2, NU5 means California, Bin 4.

It is the individual vehicle, not state of residence that determines the catalytic converter spec.

Oldblue

https://www.gmpartsgiant.com/oem-che...converter.html

Can’t see anything about CARB , there is a check your VIN

PulpFriction

The way I understand it, in NY, a CA or 50-state emissions car must get the correct OEM replacement CC, or CARB-compliant aftermarket one. But a non-CA/50-state car needs only the correct OEM replacement or an EPA-compliant one. This makes sense because it prevents downgrading a CA/50-state car.

I can see how some dealers and a shops would be confused or intimidated by this and choose to err on the side of caution.

So if I have this right, IF the OP is dealing with a CA/50 car (as was finally established in comment 15) then yeah, the replacement must be the correct OEM replacement (ie, too expensive) or CARB-compliant aftermarket (ie, still expensive.)

Oldblue

I just wonder, how many gutted cats and deleted cats are out there, and still passing ? As the O2 sensors are just before and just after the first catalytic converter, how is that second cat monitored?
I know this is a completely different discussion, so it’s not gonna help Jessica. Interesting what fastsuv posted. I’m not sure about when he certified Oldblue in NY how it passed, with an aftermarket catalytic converter.
my P0420 issue with my 2007 2.2

https://www.chevyhhr.net/forums/2-2l...20-code-58413/

Jessicasdd

Yes the flex pipe broke on my original and actually started on fire. That's why I replaced it to begin with.

When the engine was installed they used the fuel rail and injectors that came with the engine. That fuel rail caused all kinds of issues and was replaced. Then I was getting P0171. Turned out the guy put a fuel rail from a Saturn on it and it wasn't getting the right amount of fuel. Replaced that rail with a rail from an HHR and injectors from HHR. No codes for over a week then P0420. Three mechanics have told me that I just need to replace the cat now.

This is the part# and price the dealer gave me. Said my car will not pass inspection if I install the wrong one: 19418953 - $1499.97

https://www.gmpartsdirect.com/oem-pa...erter-19418953
https://www.gmpartsstore.com/oem-par...erter-19418953

Those places want a core charge but I have to send this cat back to Rock Auto for the warranty. I just don't want to spend $1500 and then Rock Auto say they won't honor the warranty and I'm out $2200 instead. The one I have now I can't get right away anyway. They are on back order everywhere and Rock Auto won't even hold one knowing I'm trying to replace it under warranty. They're not very helpful, there's no phone number to call so you can't talk to anyone. It's all done through email and their customer service sucks. When they don't want to deal with you anymore they close the ticket and you have to start all over. But I'm 3 months with no inspection so it's just a matter of time before I get pulled over for it.