The engine light comes on but it is not the half filled engine symbol so should still have full power as it's not in limp mode. Cel code was fuel mixture adaptation, I bought the car over a month ago, and one day it just decided to start doing this, has had decoke, timing chain and inlet manifold seals so far, got a feeling it could be the hpfp but, didn't know whether that would cause the problem to be intermittent?

 

Ypu could be right...when .countryman was misbehaving, it turned out that the spark plugs were not gapped right. So, take a look are the plugs and their condition. Also, when you hit the pedal, does the car feel like it wants to turn off and then it revs up?

 

car has never felt like it's going to stall always seems fairly responsive, I will check the spark plugs and things when I've got the chance.

cheers

 

Hey guys, saw lots of post about speculating solutions and had the exact issue as shown in the above video... noticeable bad but not super awful acceleration down low but then hit a wall around 4-5k RPM just like in the video. I thought based off a lot of comments it was vaccum leak or MAF sensor but logically ruled them out. I also thought it could be the diverter valve but I could still here the turbo (although it sounded like it was almost all the way open the entire time on hard acceleration). Anyways THE FIX was replacing the valve cover. I noticed some oil residue and my idea was this needed to be replaced before anything else. I ordered one off of amazon prime that had decent reviews for about 80 dollars. I installed it (took about 30-45 minutes, it was super simple) and took it for a drive... immediately had the power back. Some differences in symptoms is a briefly got a CEL (P2087 which is lean in bank 1) and cleared it the same day, drove a week without it ever coming back on but the acceleration symptom still present. I say this because I think it is totally possible to not have a CEL come on at all with this issue.

This is where I am speculating on the issue and my rough understanding may be relevant (I am happy to hear other explanations) but this is my own logical reasoning behind it. With the poor accelleration I also had a noticeable smell outside and within the cabin (it almost smelled like a lawn mower). I found a forum (may have been this one) that mentioned that and associated it to the PCV in the valve cover. I think that this got clogged and caused pressure within valve cover. I say this because it seems like that is what caused the sudden (pretty severe) leakage around the entire front of my valve cover. In addition, I read in another forum that the valve cover got redesigned (as far as the PCV) and this supposedly helped with oil consumption.

For full disclosure I have only driven a couple days since repair but did drive 4 hours in one trip and the car felt way stronger than I ever remember. It makes me wonder how long this has really been an issue before becoming totally apparent. I hope this can help someone, I am not trying to claim this is the only answer for this problem but it seems to have been my fix. I was really nervous about it being the HPFP or turbo itself like many have suggested.

Let me know if anyone has any questions and I will try to remember to post back in a week or so if the solution still seems to have been the ultimate fix.

 

Hi did you ever fix this problem?
i have the same.

 

Same issue! 2009 MCS. Doesn't freely rev and anything past 4k rpm is super slow to rev and exhaust note is deeper /sounds different. Replaced the diverter valve with new design and it was fixed for about two weeks. Bought another diverter valve and added the GFB adapter. No change. Have replaced HPFP, all four coils with NGK, all four plugs with NGK. Replaced the fuel pump filter in tank. Walnut blasted the valves. Cleaned the MAF and throttle body. Has a catch can and throttle body was super clean. new valve cover. Replaced the vacuum lines from diverter to solenoid/reservoir. Had a Akrapovic high flow cat. Because of the exhaust note change thought maybe it was clogged. Disconnected the cat at the flex pipe and test drove no change. Just changed out the high flow cat back to my stock cat and no change! Car drives fine. NO hesitation anywhere! Just pulls slowly to like 4krpm and pulls even slower after that. It just doesn't rev as freely as it did before! Thought maybe boost sensor on air intake to throttle body was bad. The yellow ceramic had a crack in it. Had the original and put it back in no change. I don't have any popping or backfiring. No timing chain rattle. Car just turned 100K. Not really any codes. Oxygen sensor codes but was from the high flow cat. Just started getting the "throttle body return spring" code. Do have a Foxwell code reader that can do live data. Also did smoke test and put the smoke into the hole where the boost sensor is on intake. No leaks. I'm stumped any ideas??