Another update.

Re-cleaned and lightly oiled the K&N filter and used 3/4 can of MAF Cleaner on the MAF sensor. No effect. Idle is still wild in gear and light comes on more frequently now. So I ordered a used MAF Sensor.

While waiting for it to arrive I took advantage of the nice weather Sunday and removed the BSH Boost Tap block and Catch Can just to rule some things out. Well, the car did not want to start after it was removed. It took three tries. After it finally started it seemed to settle down and act normal. I went ahead and unhooked the battery for an hour to clear out any adaptations and started it up again with no problem. Idle seems to be near perfect now after some test drives.

I'm guessing there was a vacuum leak somewhere in the Catch Can setup. It is not that old, been installed for about 10 months and the o-rings look good so I'm not sure the source. The engine must have really picked up some bad habits trying to cope with it thus the rough starting when everything was returned to normal, again just guessing. No codes so far and the trip to work this morning was without drama. With out the climate control on and in Drive idle sits right around 700 rpm and is very stable now.

 

Again, spoke too soon. The idle is still pretty solid but I'm still getting P115c appearing randomly about once a day. Usually on my way home from work when the car is fully up to temp. It seems to happen going into 1st gear coming to a stop after driving at highway speed. Sometimes it is pulling away from a stop. Not exactly a consistent error to troubleshoot. I did finally receive my used MAF sensor and I installed it tonight. We'll see what tomorrow brings. Hopefully no more tornadoes.

 

* MINI DTC P115C (0x2775) - Mass Air Volume Flow 'A' Too Low
The ECU is still seeing too small of inlet volume of air passing the MAF.
Which means there could be an opening / leak after the MAF allowing unmetered air to enter the engine.

Have you completed any intake system leak checks? Even with the OCC off?

Also, a heavily oiled air filter will pull oil droplets from the filter onto the MAF.

- Erik

 

Erik,

That's next on the list I guess if this replacement MAF still throws the error, which I suspect it will. I've been hopeful for a simple faulty sensor fix because that's something I can do myself but the signs are not pointing that way. Wishful thinking I guess. Maybe I can get it smoke checked at a shop in town. I have no local dealer. I'm going to check around the connections for the intercooler. I had it off awhile ago and maybe the clamps are working loose. Worth a shot I guess. I have noticed the jump of 8 MPGs since I removed the OCC and Boost Tap, plus the smoothed out idle, so something was up with that. The idle isn't perfect all the time so probably a leak. I've just not put all the pieces together in my head yet. Hopefully a bad hose or connection somewhere.

 

A final followup.

Used replacement MAF did not fix anything. I had to go into dealer for aux water pump recall so I had them look for the CEL cause while it was there. They determined that BOTH (original and used replacement) my MAFs were bad and could fix it for $600+!. This sounded suspect to me put since the replacement MAF I bought was used I figured it was plausible. I politely said thanks and gave them $100 for diagnosis. I came home and ordered a new MAF from Pelican Parts and installed it. Same f'ing problem. No way it is a MAF sensor problem. And hey, they don't take returns on MAFs...

Sooo... While at the dealer, I find out that my trusted MINI mechanic had left to join an independent shop. I truck myself over there with another 4 hour drive. He traced it down to an internal vacuum leak in the valve cover. He changed it out and all seems better now. I picked it up this morning.

So. p115c is not always just a dirty MAF sensor. Lesson learned. Plus always use guys you trust. Dealer cost me some green.

I have couple of perfectly good used MAFs for sale too...

 

This is predominantly becoming more of the source as there's been other recent threads about it.
When you say internal, was it a gasket or cracked valve cover?

- Erik

 

I'm not for sure but I assumed since the whole cover was replaced and not just gasket that there was a crack or warpage.

 

Another follow up to the follow up. The new Valve Cover did not fix my initial issue. The CEL came back on a few days later and went back to the shop.

Finally diagnosed as dirty intake valves. I had the valves blasted at the dealer about a year ago and put on a BSH Catch Can and Boost Tap block at that time. I've lost my faith in the catch can. It was catching oil but it seems to not be enough if the valves were so dirty in a year that the car was throwing CELs.

After cleaning it has been running just fine and I just rolled 40k miles on the way back from the Dragon. I'm leaving the catch can off. It will soon be in the market place as well as two used MAF sensors.

 

Have you considered the collection may be from prior to your catch can installation?
Because being a five-year old car, and only having a catch can for a year, there's potentially four years of excessive oil vapor blow-by.

How's your driving habits? Grandma style, or redline everyday?

- Erik

 

The thing is I put the CC on maybe three weeks after I had the dealer walnut shell the valves clean. I even had them take before and after shots so I know they were in pretty good shape. That's why I'm so let down that the CC didn't seem to do anything to stop the problem. If it slowed it any, it wasn't by much if they were dirty again in one year.

I'm of the belief that driving style (I'm always in sport mode!) has little to do with the DI engine intake valve carbon fouling issue. If no gas flows over the valve, how would driving style affect how dirty they get?

I'm starting to consume a lot of oil. I've not measured the exact rate but I'm guessing it's going to be close to a qt in 1000 miles which is considered "within spec". I'm theorizing that much blow-by is the main issue. It just provides more oil vapor to be burnt on the valves. I'm leaving the CC off and will probably just get a cheap walnut media blaster from Harbor Freight and try the DIY route in 10-15K miles. Or when I notice the strange pulsing idle again. There is a good thread on NAM for the procedure.

 

Do you do alot of short drives? I believe alot of the issue stems from this and not getting the engine up to operating temps enough. Just a thought.

 

Daily commute is about 20 minutes and includes several miles at 65-70 mph so it seems to get up to temp. It runs at around 226 F.

What I have found odd is for the last year or so if the outdoor temp gets above 50, my aux fan seems to always come on when I park. It may take a minute or two before it kicks on, but it seems to always do it if I drive it hard or not. Lately I've been letting the car run for a minute or so when I park to help it cool the turbo, but I'm not sure if it is doing any good. And I always let it warm up in the morning to low idle before I pull away.

I did add a can of BG MOA oil additive when I did my last oil change (about 5k ago). I don't know if that has caused in the increase in oil consumption/warped valve cover/nasty intake valves I've had since then or just a coincidence. I just hit 40k on the way back from the Dragon in this 2007 so maybe I was just due. I knew in the back of my mind I didn't buy the MINI for the reliability but all the issues do wear on you after a time.

 

I am having the exact same issues as TheCheatOSX had. I also have a BSH boost tap and catch can. I will post my findings to see if they coincide with the above remedy

 

I think your in good shape now. The issue was in your valve cover. There is an internal diapham that fails. If the valve cover is bad, you can clean your valves and 10k later they are wiped out again. Eventually the valve cover gets so bad you can here it sucking while running or when ya shut the vehicle off you can here the vacuum bled off.