Hi,

I've been combing the forums for a while here, but don't post often.

Hoping R56 guys can help as well since we share so much in common mechanially.

Running a 2010 (N14) R55 S with intake, IC, VR tune, and downpipe back exhaust. Its an auto that is always in manual mode.

Car's been running fine for the past year when I installed most of the mods. Recently had to replace the lower engine mount bushings (with Powerflex) because my NM air filter guard was flexing into the firewall on throttle.

Lately, I've been chasing a P115C CEL. For the last two weeks, the CEL comes and goes, but is staying more persistent now. After reading many posts on various Mini forums, I cleaned my MAF. CEL persists. Its the only CEL I'm getting. Additionally, I've heard it could be the valve cover, etc. That was replaced by the dealer about 10K ago, so I'm trying to rule it out as its pretty new. Car only has 60K miles on it. Also, already been thru 2 walnut blasts since 25K and I now run an oil CC. Additional symptoms:
1. rough idle (could be the powerflex busings though)
2. surge/burble sound when coming to stop - idles smooth after complete stop
3. Power (turbo) drops off - but its not limp mode. Normally, I can hear and feel the turbo kick in from part to full throttle. Lately (and its progressively getting worse), I'll give it gas, and it behave like an NA car. If I release throttle and push again, it will usually reset itself and I'll feel the turbo. With the intake, the diverter valve is loud and noticeable. When in "NA" mode, I get a slight diverter blow off, but not forceful at all.

I've also heard that the code could be indicative of the throttle body. If its sticking, it could be causing the MAF to not properly read airflow based on throttle position (or could it be the throttle position sensor?).

You guys have any thoughts before I just start replacing parts? In all the other posts, I didn't any symptoms like my #3.

Thanks,
Sean

 

what is the description of this code?

 

Per Bentley, There are several P115C entries with different MINI FCs, but all resolve to: Mass Air Volume Flow 'A' Too Low

 

Yes, thank you. That's correct. And depending on the scan tool, you also typically see another "hidden" code 2B5C Air-mass sensor, plausibility - which I had as well.

My codes did go away after leaving the car with my mechanic for two days. I had previously cleaned the MAF, but the code remained. After smoke testing and seeing no leaks, he suggested we replace it, we did, and the codes remained. Inspected throttle body, no cracks. Noticed the final air tube before the throttle body was pressed against the firewall and getting cut, but there was no penetration/failure. Eventually adjusted that one tube and tightened every o-ring between the air filter and the throttle body. Problem went away. I still have a bit of oil weepage on the valve cover. Dealer said its under warranty, so I'll take it back in after I smog it.

Infamous $700 loose screw...

 

Very glad it is fixed. These kind can be so vexing!