I've had a P0297 code hanging around for a very long time on my '05 R50. I changed both O2 sensors when I bought the car, and everything was fine for about 10k miles until this code popped up. I tried another new O2 sensor to no avail (I tried front and rear). I can only assume the cat is dead. The car has almost 180k miles, so it's probably about time, yeah? My question is, what is the best, inexpensive way to do this? She's no beauty queen and has some other issues, so it's not worth going brand new OEM. I will be doing the work myself, as I generally don't trust shops with my cars/bikes.

Thanks

Edit: I should probably add, I just moved to California (which is why I'm finally getting around to changing it) so it must be able to pass emissions.

 

Well, if you didn't live in CA I'd advise you to seek out a used converter from a Mini salvage yard ideally from the same model type/year of car. Handle the converter carefully, shake it to see if anything inside rattles (if it does you don't want it), see if anything falls out (if anything does you don't want it) and otherwise looks to be in good condition then buy it and continuing to handle it with care go home and remove the old one and bolt in in the "new" one and motor on.

Trouble is in CA apparently you can't do this. I think.

Here's what I could find on this:

EPA considers it a violation of the policy to install a used converter from a salvage yard or sell it for reuse unless it has been properly tested and labeled. Similarly, it is a violation to install an untested used converter brought in by a customer, even if the customer insists that the used converter came off his/her vehicle.

Salvage or junk yards also would be considered liable for causing tampering if they sell converters that have not been tested or do not meet the requirements outlined in the policy and if the converters are subsequently installed by parties named in the Clean Air Act as prohibited from tampering....

....Used converters are only required to meet the performance requirements at the time of sale......

.....Re-manufacturers of used converters may only use OE converters and must test each converter on a bench test to show that it is still performing satisfactorily. Both new and used converter manufacturers must comply with certain record keeping and reporting requirements. They must also have a system to notify installers of the requirements.

In CA if you don't want to buy a converter from the factory then there are CARB approved suppliers of converters for your car.

Here is a link to a PDF which lists companies granted CARB approval to sell replacement converters.

https://ww3.arb.ca.gov/msprog/afterm...xemptcat09.pdf

MIni does not show up. Just BMW. Could be a BMW converter is the correct one for your car. Or just visit the web sites of the various converter companies listed: Magnaflow; Tenneco, Catco to name 3; and plug in your car's details and see what comes up.

 

So it looks like it would be illegal for someone to *sell* a used, untested cat, for a shop to install one, or for companies to re-man an aftermarket one. However, if I were to buy a used one from outside CA and install it myself, it could possibly be deemed "illegal", but if the car passes emissions, who would know? I mean, if someone bought a used car and unbeknownst to them, a former owner had installed (or had a shop install) a used converter, how would the current owner know? Or, if someone had performed this work outside the state where it is legal, is it now "illegal" to drive the car in CA so long as it passes emissions? In my mind, if it passes emissions, no eyebrows should ever be raised, and even if it fails, I assume you'll be given X number of days to fix and re-test before your registration is pulled etc. I can't imagine someone somehow trying to verify whether or not the cat is original to the car, especially for a 15 year old car with 180k miles.

Good info either way, I'll peruse the list. Thanks!

Also, what does the community reckon is a decent mileage for a cat? For example, I wouldn't buy a used cat/header off of a car with 200k, but 50k *should* have a usable cat, right? How about 100k, 125k etc?

 

We offer a CARB legal cost effective Magnaflow header that works well.
https://www.waymotorworks.com/magnaf...arb-legal.html

 

I'm sure that's a wonderful setup, but wow! $800 exhaust on a 15 year old car car that's probably only worth a few times that seems like a bit of a stretch!

 

 

Some might argue that this is an upgrade as well as a replacement and when you put money into a car like this it is not what the car is worth, but what it would cost to replace the car that I think about. With new cars running over 20 to 30K $800 is chump change.

 

True on both counts. And as hard a pill as it is to swallow, I do love the old girl, and have already sunk more money/time into fixing her than I'd care to admit. It's certainly on the short list of options, and thank you WMW for the link!

 

Regarding your first paragraph: I know nothing. I see nothing. I hear nothing.

As for the question of what is a decent mileage for a converter?

Converters can fail at any time. But federal emissions law requires the automaker cover them from new to I think 8 years/80K miles.

I have driven a number of cars with converters anywhere from 28K miles, 50K miles, 3 to 150K miles, and one car to 317K miles and only one converter developed a problem. Something bounced up off the road surface a hit the exhaust manifold right at the converter housing -- hard enough to put a nice ugly gouge in the stainless steel housing. This impact caused the converter brick to become loose. Most of the time the only indication there was something wrong was the brick or something in the converter housing buzzed -- sounded like a loose heat shield -- when it got up to temperature. Towards the end it manifested a dull knocking sound at cold start until hot then the buzzing took over. However, the brick remained in place and worked just fine. Most of the time. But once in a while it would shift position ever so slightly and trigger a P0430 error. But as mysteriously as it shifted out of position it would shift back into position and resume working just fine. Eventually the knocking and buzzing got so bad I replaced the converter.

 

I haven't noticed anything nasty with it beyond the P2097 that doesn't seem to be O2 sensor related (can't think of anything else it could be...?) I did have to replace my exhaust a few months ago (long overdue) as the many Michigan winters rotted the muffler and hanger assembly out completely. She sounded like a Civic with the full fiberglass body kit treatment! I haven't seen or heard any holes in the cat, but I imagine 15 years of warming up/thawing out and running rich at idle might cause a slightly premature death for a cat...?

 

You said "P0297" in your first post. I took your comments there was a converter problem at face value.

The P2097 is not a code with which I'm familiar with. Let me look it up....

P2097: Post catalyst Fuel Trim System Too Rich (bank 1).

That doesn't necessarily point to a bad converter.

You have replaced the O2 sensors. Did you get the right ones, OE sensors? Sometimes the OEM sensors just don't perform as well as the OE sensors.

There are cautions about handling sensors avoiding using any thread lube like anti-seize -- my limited experience is OE sensors come with proper thread lube on the threads but OEM sensors come "dry". And of course avoiding using any cleaner on the sensor or even the connector. Some sensors breathe through the wiring from the sensor to the connector and an electrical cleaner can foul this breathing function.

I note you replaced some of the exhaust. An exhaust leak can play havoc with converter (and sensor) function. You must be very sure there is no leak. And it doesn't have to be a great big gaping leak either.

The converter is subjected to a bit richer running upon startup and shortly after but this is intended to help heat the converter as the excess fuel is burned in the converter. Generally when the cold idle speed drops to near normal and if present if the secondary air injection pump shuts down (this is used to supply outside air to the exhaust to help the excess fuel burn in the converter) the engine controller has switched to closed loop mode and the engine and this includes the converter is being fueled at around a 14.7:1 ratio which is the air/fuel mixture a healthy engine generates exhaust gases which are most effectively processed by the converter.

'course, as I touched upon in my earlier post the converter can fail at any time, can wear out, or more accurately over time just lose the catalyst metals that cover the interior walls of the converter. These are bonded in some way but over time this bonding can degrade and the converter sheds what make it work. A converter can get fouled if leaded gasoline is used. It can also get fouled if oil with too much ZDDP is used. (The ZDDP can form a glass like coating on the working surface of the converter's interior.)

Stating the obvious but given how expensive a replacement converter is you want to be sure you have eliminated any other possible explanation for the error. (No experience with Mini but with other cars I had access to the factory manual for OBD2 errors and often (always) the error code was followed by possible fault causes, ways to test for these, and futher steps to get to the bottom. I'm pretty sure the Mini OBD2 error reference manual is similar so there can be a bunch of things, or just the right things, provided to get to the bottom of this.

Sometimes an accommodating tech can print out the section that covers a specific error code and share it with you. If you find one bring donuts the next day, enough for the entire service department.

 

I replaced both sensors when I bought the car (she was throwing an O2 sensor code when purchased at 153k, one of the reasons I got her cheap) with what I've read should be the proper OEM sensors, NTK. It was problem free for about 10k miles after that, before throwing the 2097 code. I bought another of the same O2 sensor, thinking perhaps I got a lemon, but after trying it both upstream and downstream, nothing. If I reset the SES I could (and still can) start the car without the light coming on, but at the next start it would throw the 2097 and stay on until I reset it again, and only stay off for one drive cycle. Every once and again (every few months), the SES will turn off while I'm driving and stay off for up to 20 miles, only to come back on. The last time it turned itself off was last November. I get very thorough 25+ mile drive cycles almost daily, so it's not a simple drive cycle issue either.

A few thousand miles AFTER the incessant 2097 popped up (and after the 3rd new trial O2 sensor) is when my exhaust bit the dust. I have since replaced everything from the cat back with a very good condition used OEM unit from a wrecked car (straight and true, no rust). New gasket, hanger etc. If there's any leaks in the system, they must be very tiny. I've done my best to find one, and can't, of course I'm not perfect! It seems to me that besides an extreme rich fueling issue (which would likely kill the cat), it's unlikely that a rich downstream O2 sensor would be from an exhaust leak rear of the cat. Granted, I didn't pay as much attention as I probably could have in my automotive emissions college courses!

 

What is your gas mileage like?

 

Right around 30.

 

I didn't see it in the thread ( could'a missed it) so I am assuming your driving a turbo and that MPG is about what you'd expect for the kind of driving you are doing. Was hoping to see if there was a fueling issue by way of MPG.
If you're driving a normally aspirated, then 30 is pretty low and I would look further upstream.

 

Stock '05 R50 (NA). I do 90% freeway driving between 65 and 75, my mpg have been about 30 ever since I got the car at 153k. At 177k or so, she's getting a little long in the tooth. I wouldn't be surprised if my compression is a hair low at this point, but I've never checked.

 

I *love* Cali... some of the Cats (or some performace parts) are california "compliant" but are not CARB approved so they cant be shipped here. Im just glad I'm registered out of state and dont have to deal with the smog crap.

 

Welcome to the life of an enthusiast...

Semper, devil. Ship stuff to relatives and then ship it on-base or to your residence. Costs extra, but with registering my car in MA while I was on Camp Pendleton, I did whatever I wanted. There's potential for PMO to give you a hard time, but it's not much of a stretch to be more intelligent than them and be able to quickly educate them on the laws and why they're wrong. I'd offer to help if I wasn't on the East Coast (shipping would be expensive for no reason, where if you have a friend of family in Nevada or Oregon, it's simple).

 

Just dont get stopped by PMO.... most of the time I see them get someone is not coming to the 3 second full stop🙄.

 

At the gate. Technically you're required to be in compliance with all federal and local / state laws while aboard any installation. This includes requiring SMOG for base registration for Miramar and Pendleton.

Having said that, I never registered my cars on base, never smogged them, etc., but just want to give a heads up on what's actually in the base order. The lance coolie at the gate ain't gonna care, but some motard who didn't get any from their wife last night could be a hassle.