Aftermarket cats and O2 sensors for California
 

The OEM pre-cats and O2 sensors for CA are outrageous (~850 per side for cats and ~200 per sensor). Does anyone have experience with the aftermarket cat assemblies (comes with both plus pipes for ~400), and Bosch O2 replacement sensors (not univeral, OEM replacement for ~65)?

Is there a difference I should worry about? Do the non-CA cats have threads for all four sensor left/right/infront/behind?

Cheapest OEM for both pre-cats and all four sensors is about $2600!!! (not even list, and that's just parts)

Thanks for any help or advice,
Jeff

Just put a new oxygen sensor on my '95, which only has one, left side, pre-cat. I got the California super-duper one, a Wagner, I believe it was, for around $85.

So far I've haven't had to replace my cat, although I've looked them over and gotten the same sticker shock as you're experiencing. California passed some law a while ago that all these pieces have to be manufacturer-supplied, which naturally means top-dollar. I'd love to have been able to sit in the room when that bit of legislation was written, but that's a show for another channel.

I think it comes down to a few things. One, how do you feel about following the letter of the law? Two, what are the chances of you failing a physical inspection of your cat if your cat's not one built and supplied by Mitsubishi? I believe most smog shops would just glance under your truck to see that one's there. Period. Naturally, I'm not advising you one way or the other; we're just two guys having a conversation, like they say on the cop shows on TV.

You asked about threads. I believe the difference is in whether they come with a Montero-friendly connector on the electronic end or are they a universal fit which requires trimming and matching the four wires to the ones on your harness. Every oxygen sensor I know of threads into the pipe; what else would they use? I hope someone will correct me if I'm wrong about that.

Bottom line, I think whether you use California-approved equipment for your emissions equipment or not is a decision that you alone will have to make.

Let's hope some other denizen of the Golden State pops in with another opinion:)

Of course it's my decision, but that isn't the question. In order to make a decision, I need to know if it works and what the experience is. If my ECU is CA only and there are CA specific calculations for O2+cats that I'm going to screw up by going aftermarket then I have no choice. If anyone has replaced an O2 with a Bosch (connector wiring notwithstanding), did they have any ramifications, and any ramifications in CA? Same question for pre-cats.


Thank you for the opinion, but the question still stands...if anyone has real experience in this area for a 2002 Montero Limited or equivalent?

I have no problem with the "OE Type" replacement o2 sensors. This is the best place that has been good for me in terms of price and availability.

http://www.oxygensensors.com/

The big problem are the CATS. First, due to that law that passed not too long ago CA is VERY STRICT on aftermarket cats. Distributors and shops also know about this because that law says they could be fined huge if they install or distribute non-CA or install ones not specific to your vehicle. Thats why youll see a lot saying EXCEPT CA, or CANT SHIP TO CA.

I went to the state ref with one of my other vehicles, I had the cat replaced, I passed emissions just fine, BUT because the carb and EO# didn't match and say it was for my car.. FAILED. I went to the muffler shop and just showing the failed sheet and why they know the seriousness of it and replaced with the correct one labor free.

Of course the above scenario is the extreme. I need to replace my main cat (one under driver/2nd row) cause its rattling, but as you know it too is $$$$$$. I can EASILY find a universal cat. that is way fcheaper, the problem is finding a shop who will weld it on for me.

Thanks, good info. I have 130K on my Monty, I may just live with the CE light, I just passed smog only a couple months ago so I'm good for a couple years as long as I can monitor for other codes with a scan tool. Somebody posted here that a bad cat can ruin an O2, but I can't understand that and will ignore it for now.

Gotta think about this one some more...

220K miles on the original O2 Sensors but had to replace both pre-cats at 160K and 180K. The pre-cats definitely go bad - not sure about the O2 sensors. You need to tell us what codes you are getting. There is a sequence that OBD goes through and if the Cats are not working the O2 sensor test is aborted. Please post the codes.


As far as pre-cats, I bought the parts from www.mitsubishiparts.com. Not cheap but way less than normal dealer parts. Not too hard to replace.

A local muffler shop said CA had approved some tiny aftermarket Cats that could be cut and pasted into the downpipes but the overall cost was only a few hundred less and he wouldn't guarantee it would pass smog.

Ron

Ron, your "few hundred less" you make sound like chump change lol.

If I heard that I would say go for it! haha. I actually did though, passed smog, as long as everything else in your car is running normal. I don't think any muffler shop, at least smart ones, would "gaurantee" passing smog with any part they install. But it depends on the meaning of "pass smog", PASSING VISUAL then yea I would say that too, no gaurantee on the universal weld on due to all the strict new laws. But the actual emissions testing--again as car is running normal and the cat is actually a cat with the filtering elements should be fine.

jrmdr said: A local muffler shop said CA had approved some tiny aftermarket Cats...

I haven't heard this tidbit of news before. Is it legit?

I just bought a Denso (OES for Mitsu) oxygen sensor for my 2003 Sport for $32.50 at this place in Orange County (CA). They have great prices on Denso O2 sensors and they are a direct, exact, plug-in replacement for the OE part. They have other brands as well.

http://www.apwonline.com/shop/

YES ABSOLUTELY, since jan 09..

what he meant was there are now only a VERY FEW "UNIVERSAL" selection of cats that can LEGALLY be purchased and put on.. and he continues that quote by saying---which i mocked him on--- "a few hundred less" than OEM.. a few hundred is still a few hundred hahah, thats a big chunk..

universal cats were dirt cheap! they just cut off the old one and weld into existing piping.

NOW.... due to the new law, there are very few of these universal cats that can be sold/used in CA, which makes owners have no choice but to get OEM ones which are like $500-1000!!!!!!!!!!!!!!!! I've looked. Universal cats cost like $100!!!!! Even the aftermarket CA approved cats are still a grip of money..

Here is official documentation of it.

http://www.car-sound.com/04basics/04california.asp

HOWEVER, if you find a "COOL" muffler shop, and they can obtain universal cats, they will work and you will pass-- UNLESS the smog place/tech is anal as F|_|ck and check the EO/CARB #s which shoes not to be a CA complaint cat nor for your vehicle... EVEN IF YOU JUST PASSED THE EMISSIONS TEST, they will fail you.. how do i know.. im in Ca, and ive had this happen to me. ha