Mickey, we are really fortunate to have Matt so near us. He's helped me in at least two instances sort-out issues...

Also, I'm not so sure you'll want to trailer your MINI to his place. It's quite a trek through plenty of twisties, incuding some fairly tight ones, as I recall. Maybe you can meet him where he works. He'll chime-in soon enough...

 

I'm taking my business partner to the airport (SF tomorrow). Then my schedule opens up. Anyway, I live up by Alice's restaurant (Hwys 84 and 35) and now work from home.

I'll PM with details....

Matt

 

Tony,
If you still have your stock cat around -- I'm interested.


Mickey

 

Mickey, I don't have a stock cat per se, but the stock header, with the cat. I've been keeping this unit just in case my SuperSprint with stock cat for some reason doesn't pass the visual inspection...

If you need just the stock cat to flange into your Militek, I'd check the local salvage yards for a stock header. Heck, some of local MINI shops are bound to have some just lying around. I just got back from LA and I saw a few in the various shops/places I visited...

Sounds like you've concluded it's the cat. If so, I'm glad you finally pinpointed it.

 

I think I'd replace the pre-Cat O2 sensor while your at it.

As far as all the "tune" comments, I was under the impression that the Dimsport tune only effects open loop performance and the closed loop settings were not accessible.

 

Sorry for your troubles . Dealt with this sort of thing too many times myself. I have read all posts and have some input that might help.
Currently , there are no 'CARB legal' aftermarket header's for use in California on a MINI. Aftermarket headers tend to have "Ceramic cat's" [$] ,that have less Platium/Irodium ,etc. in them than "Metalithic cat's" [$$$]. Ceramic's burn up much quicker.
The combo of header and exhaust have less back pressure wich takes longer for the cat' to light-off, if you drove a short distance, or the car sat
at the test facility for awhile, it could fail. I've seen this in several times,different makes & models with similiar exh. set-ups.
Change the header back to stock & make shure to run it pretty good for 15-20 min. Make shure it's HOT!.Don't Let Them Park It For Half-Hour, Then Test !
Your problem should go away.
Also, Smog Tech.'s should not be making issues out of CAI's on MINI's. They do not affect Throttle Bodie or Air Flow sensor placement. As long as your crank case breather hose is still hooked up , the California Smog Manuel consideres this a "NON-ISSUE"
This guy sound's shady' ,Go somewhere else.

"You don't know the power of the DARK SIDE"

 

Second smog retest and failed.

I put 100 octane in the tank.
Sea Foam treatment.
New O2 sensors
New plugs
Fresh oil change
Stock air filter (removed CAI)
Still throws a P0420 code. Catalyst efficiency.
No noticeable engine problems: idles fine.

I had taken the car to a different smog station that was recommended by a BMW/MINI repair shop in Dublin.
The car was driven for 40 minutes before the test.

Second failed test results were almost the same numbers as previously posted.
Some improvement except for nox, there was no improvement with nox.

I have a Miltek header Cat. Installed about 3 years ago. I guessing around 10K miles on it.
After speaking with a Miltek distributor, indications are the cat is shot and is not under any kind of warranty.
Also, I cannot just order a new or replacement cat because of new California laws.
I have to reinstall the stock header/cat.
I just painted myself in a corner.

 

And deinstall it - once every two years...

 

If want the name of a shop that you can bribe let me know. It will at least get you two years until you have to do it again.

As for as a replacement cat the new rules have made it difficult but not impossible. Have someone outside of CA buy the parts and ship them to you.

Everything you have posted is pointing to a bad cat at this point.

 

Bad cat.

 

Mickey,
I still have my stock header/cat if you need to borrow it.

Jim

 

Well, got it to pass smog.
Had to re-install the stock factory header/cat. Good to go.

The Miltek header/cat gave up the ghost at Laguna Seca. I could not get over 5,000 rpm. A white emulsion was dripping out of the exhaust tips.
It was clogging the exhaust. Sounded like a turbine. Packed it up after the first run group and headed for home.
Gutted the Miltek header/cat. Car runs really nice without the cat.
But, I had to install the factory header/cat to get smog.

Yep, will have to repeat this every two years.
For now, I need a back up street legal car.

Thanks folks for all your help.

Mickey

 

-totally true, there are many 3rd party co's selling CARB complient CAI's for many cars that are basically K+N cone style air filters, ..in fact I just saw at a Lexus dealership that they are offering an option to have the dealer install a CAI if you want when you purchase your car (it's part of their high performance options). ...totally smog legal. I think the visual thing is BS and this guy didn't know the actual laws, ...most CAI's will not effect smog output at all.

For the header issue, yeah, California sucks for their strict smog codes, ..for this reason I will never install a high performance header on my MINI, -just too much of a pain in the butt.

sorry for all the trouble you went through.