I've had this pesky code for many months, and I plan to finally make some time to get to the bottom of this soon; ideally this weekend, IF I can finish these dang taxes!

My CarChipE/X is able to clear the code, but it comes back, almost always when cruising on the highway (6th gear, around 3,300 RPM).

My mods (relevant ones):

-15%/+2% pullies
UNICHIP
HAI
DFIC
400 cc injectors
NGK spark plugs (1 degree colder)
Kingsborne spark plug wires
SS ceramic-coated header, w/ stock cat
SS center pipe, with resonator
Borla Turbo muffler straight out the back (battery box removed)
=====

The DFIC and spark plugs were installed fairly recently, long after this problem had already surfaced, so they should not be considered.

My UNIChip is pre-mapped for an intake, exhaust, 15% and IC. I am of course thinking that I might eliminate this first simply because it is easy to do...

The injectors? an O2 sensor? a failed or failing cat? I'm open to some ideas, and I truly appreciate the input! Thanks.

Oh, a search here and on MINI2 yielded virtually nothing...

 

The MAF (Mass Air Flow) Sensor is dirty or faulty?

http://www.obd-codes.com/trouble_cod...gen-sensor.php

Really hard to tell sitting here at home. Good luck on the taxes, you should have had them done months ago.

 

Wow, JustGo4It, that is helpful. Not sure how to clean a MAF sensor, but I'll give that a try first. I really appreciate it.

Don't get me started on the taxes. I actually finished them a couple weeks back, but in doing so realized that I made errors on previous years! These are in my favor, which is the good news. The feds let you go back 3 years, and CA 4 years. Doing amended returns.. But, it will net me some nice dough, so I'm all over it!

Back to the MAF sensor, I really think this might be it as one time I oiled my filter too much... I will report back, and of course remain open to other ideas. Thanks again.

 

clean the MAF sensor using a throttle body cleaner.

Here is a good read.
http://www.gatewaycleanair.com/mecha...4/dirtymaf.htm

 

Well since are cars are MAP/TMAP not MAF based....

I too have thrown that code. I had a similar setup with 440cc injectors and switching back to smaller, in my case, stock, injectors fixed it. For your info, the "bank 1", reference is an idle reference. If it was under throttle, it would be "bank 2".

Hope that helps.

 

You know, while showering, I just remembered that our cars utilize MAP, not MAF sensors, right? I need to go hunt-down some threads...

EDIT - Just saw where AZMCS confirmed before me! Thanks. I'll look at the injectors then...

 

yup; i was gonna chime in and just say damb those are big injectors for a 17% set up ~!!!!!

 

I had the exact same problem. When cruising the light would come on and it would be the P0172 code. At first it was once a week but progressed to a daily situation. I replaced the o2 sensor, the second one past the catalytic converter and have not gotten the error since.

 

Gary, thanks for your input on this. I'm contemplating trying this first, and if that's not it, then the injectors...

From what I recall, changing an O2 sensor entails the wire and connector also. That is, there is no disconnect at the sensor itself... If you don't mind, what was the cost for the appropriate sensor?

Come to think of it, having a header ceramic-coated, including the inside, might make for gumming-up on the O2 sensor, I would think...

Thank you.

 

Where did you get that? BMW has always used bank 1 and 2 for V engines or inlines with multiple manifolds/02 sensors.

Tony, Check your fuel trims.

 

How do you recommend that I do so (check fuel trims)? Sounds like maybe I should remove my UNIChip first...

Thanks for chiming-in 002! Was sort of hoping you might

 

Tony, just a couple thoughts...
About your injectors, I believe they are a little large for your combination/power level, and would possibly be the cause for your rich condition. But at the same time, from what i've read, unless you have specific mapping to utilize the larger size, you are not getting all you can from them.

About your header, the ceramic coating definitely keeps more of the heat in, and at the same time transferring more of that heat to your stock converter, which it may or may not have been designed for it. From what i've seen on other vehicles(excluding the MINI), the secondary(post cat) O2 sensor is basically just there to make sure the cat is converting, and will only throw a code when the converter is not doing it's job.

I'm going to assume you are using the stock, post cat O2 sensor bung. What about the pre-cat bung? Was it already in the header? or did someone install it for you?

 

Injectors...

You're running modified injectors. They don't have the same spray pattern as the stock injectors... big no no. I wouldn't run anything other than JCW (On the recommendation of MANY people).

 

Good to hear from the new Daddy! Thanks.

The SS header has a bung, which is pre-cat. I have the stock cat which includes the the stock bung (assumption correct) after it...

Fuel trims, O2 sensor, UNIChip not tuned to mods... I'll tackle the easier ones first.

FWIW, I installed the larger injectors months before this code surfaced, so I'm totally certain that it's not simply their size, or increased flow rate. If there was a failure with an injector, that seems possible though. I believe JCW's are 380cc, and this is for a 13 or so % SC reduction. A 15/2 equates to more of course, not 17 as some think, but more like 16 something, if I recall correctly. A 20 cc delta (380 vs 400) on an increased pullied MCS I doubt is the culprit here...

 

This (the spray pattern) I have heard! What do JCW's cost?

 

I got this when my o2 sensor was acting up went away after o2 sensoer replacement

 

Tony,
Most scan tools that read sensors can do this. Don't change anything if you plan on using the info from the dme adaptations, you want to see what it is trying to do.
The fuel trims will tell hoe hard the dme is working to lean it out and in which load range.

Braking it down into systems will help to keep you focused; Air metering, fuel control and 02 sensor feedback, etc... Try to visualize the sensors involved and how they could generate the code. What would you do to intentionally generate the code if you had to. You must become one with the dme.

You also need to figure out if you are actually running rich or if the dme thinks it's running rich (because of programming parameters).

How does the car run?

Like I have mentioned to you before, it is hard to diagnose via internet, but I will do what I can.

 

Looks like I'm in business as my CarChipE/X can log fuel trims!

Bank 1 - short term
Bank 1 - long term
Bank 2 - short term
Bank 2 - long term

Should I log all 4, or just the two Bank 1's?

Car seems fine. I do sense it missing sometimes though...

Thanks much!

EDIT - How about O2 sensor voltage (B1, B2 S1-S4)?

 

I would be very suprised if you where able to log bank 2.

Look at long and short term at idle or very light throttle then again at medium throttle and note the numbers. If you can't see the data in real time, be sure to log throttle postion or load to give some perspective.

The 02 sensor is harder to explain, so start with the trims.

Edit: Did you ever test the fuel pressure the last time we chatted?

 

With the power Longboard was making (230 to the wheels) he was just bearly maxing out his stock injectors. 380's will work up to about 250 or so i'd imagine without any duty cycle issues.

 

I can log 5 variables at one time. So, this is what I chose:

Short term fuel trim (B1)
Long term fuel trim (B1)
Fuel pressure
Fuel system status

The 5th selection is speed.

This thing logs every 5 seconds, so not exactly dense...

Oh, I never did log fuel pressure before. As you might remember, that previous issue was resolved by soldering a couple wires coming off the coil. Splicing into these had caused some serious problems over time...

I will do some logging tomorrow! Thanks again.

 

$339 (Without core exchange) . I seem to remember them being cheaper somewhere though

http://outmotoring.com/john_cooper_w...injectors.html

 

That seems a little steep, but hey, if needed... Thanks for the info.

As per 002, I'm going to do some data-logging first. I'll report back with the results...

 

yeah good point on the time line . it would've shown up sooner . so maybe the cat took a dirt nap .

 

IIRC, the injectors originally came with the JCW airbox - people were splitting them up to justify getting the airbox. Might be worth a posting in the classifieds to see if someone has a set.