Good day folks. Yesterday, while driving home, my 2010 MCS threw a CEL. Didn't notice a performance change nor anything visual or audible. A few minutes into trying to figure things out, I finally noticed a very slight loss in power and the wastegate not opening ( not able to hear the sound it makes ). 122k miles on it so i'm kinda inclined to think that the turbo bought the farm. Or is it possible that its just the cutoff valve? Its the weekend so the only diagnostics place available to me is autozone. Anyone know if their diagnostics is good enough to find a problem with the turbo if it turns out to be the turbo? I do have a diagnostics tool plugged into the port and it does not pick up any codes. Live telemetry shows turbo APPEAR to be functioning. Thanks in advance for any help you might be able to send my way.

 

Really need to pull the codes before anything. Call AZ and ask if they have a BMW code reader. Once you get the codes lots of smart people here can help.

 

Because it is the weekend, AZ is about the only place i can go and get it diagnosed. Thanks!

 

If AZ can't pull BMW codes it isn't going to help. Because you have a CEL you should have active and probably stored faults.

 

ok....went to AZ and oreillys. AZ, according to the guy at the counter, is able to pull BMW codes.....but none showed up. Went to oreillys where they have a Bosch diagnostics tool. Was a lot more involved in the diagnostics......It pulled code but it was for the brakes and brake sensors which i havent reset when i had a brake job done several months back. Nothing with emissions or anything else. Weird thing is, going home, the CEL was gone and going by feel, the power was back to 100% although i am still not hearing the wastegate. Is there such a thing as replacing or fixing JUST the wastegate? I am guessing that because it is a part of the induction process, that the turbo would also be faulty? Will have to wait til monday to go to a Mini specialist for a diagnosis.

 

I have the same model, same year, with almost the same mileage. My turbo diverter valve went out a few months ago. Symptoms sound similar and it's a very common failure. The code I got was "28AA DME: Bypass blow-off valve, plausability". It's a cheap ($40) easy DIY fix if that's your problem.

https://www.ecstuning.com/b-pierburg...658636606~pie/

 

Diverter valve was exactly what my problem was also. A non-BMW shop quoted $4000 to replace the turbo which they said was bad. This is why I say get the real BMW codes. They will usually point in the right direction.

 

Hey would you happen to know what size torx screw holds it in place? is it a torx to begin with? Thanks!

 

Good question. It is a 5 mm hex, not a torx. And whatever you do don't drop the bolts. https://www.northamericanmotoring.co...your-mini.html

 

Well i replaced the diverter valve and the boost feels like its back to normal. However.....i am not hearing the hissing from the diverter valve when you shift and let go of the gas pedal. I think i might be hearing a very short hiss but nothing like the normal way it does it.....

Which leads me to think that the cutoff valve on the other end is the problem which pretty much means i need a new turbo.

 

The hiss from the diverter valve went away when I replaced mine as well. If you're building boost and have no CEL, my bet is your turbo is fine. I miss that hissing sound, BTW.

 

Yeah...it feels weird not hearing it. Boost is there....torque is showing the boost when i am on the gas

 

Sounds like you found your problem. Just curious, did you use the new style valve or the old style?

 

went to the mini dealership and grabbed their "genuine" diverter.

 

Well both designs are "genuine". The older style used a rolling diaphragm. The newer style uses a poppet style. I never heard the whoosh with the older style but did start noticing it with the newer poppet style. I was just wondering if you remembered what you put in since it seems to have quieted down for you.