Ok, so I searched and searched, was not finding a link between what I am experiencing and what ahs been posted on the boards. I do apologize if I have missed something.

Time line: Friday night, @ 8:22pm CST with a temp at 89*, very high humidity, and sport mode on, the half power engine light came on the tach. I was accelerating from a stop to 45mph, it appeared at the shift from 1st to 2nd. I pull over, check the engine bay for any signs of gremlins, didn't see any on this glance. Shut down my car, restarted, put sport mode back on, and drove it home softly.

Get home pop the hood and look it over a little more, still not seeing anything. I start it back up after about an hour sitting, no more half power light. I put some revs into it, not moving, and above 4K it seems to loose power. But still no light. I put sport mode on, do the same and as soon as it hits 4K, half power light.

So I think to myself what could cause this. I know the R56 has a HPFP issue, so I start searching here. I do not have starting issues, I don't hear a vacuum leak, and the car drives ok-ish. Just seems like it needs a cup of coffee.

Sunday, I take the wife out for some shopping, with no sport mode. After some heavy driving, still no light. I put sport mode on, go around a turn, light is back, and it feels like I have lost boost. I get to the stop light and now I can't really hear the turbo spooling. I shut the car off, turn it back on, leave sport mode off, light is still on the tach, and now I can hear my turbo.

Monday, at 7:45am at 85* mild humidity, I go to work. There is a clear stretch of road about 1/2 mile long. No cops out so I push it with sport mode off. No light after going through all six gears and doing about 85-90mph. So in my mind it was a fluke. Turn sport mode on at the stop light, make a left, accelerate past 4K, and now it's back. I yell at my car, scare the mini driver next to me and continue on to work.

Lunch, 98* high humidity, no sport mode. No issues home. Turn sport on as I park, and rev past 4K, and the light is back. Some more yelling. I eat with the wife, browse around here and a few other sites for more information, not finding a like post. Leave the house and head back to work. Light is still on but can hear the turbo. No sport mode, and I push it, beat on her, I get to the last intersection, still no sport mode, I hear no turbo spool. I get to work and the light is back off, and I can hear my turbo again.

I am at a loss of which way to go. I have an appointment with MINI of the Woodlands on 7/30, but want to try and figure this out before hand. No shop around here have a reader than can read mini codes. If it was the HPFP, shouldn't I see random RPM's? If it was the diverter valve, shouldn't I hear a hiss or vacuum leak? If it was the vacuum lines, should it not through an actual CEL code?

Update: Ok, seems like it is the diverter valve. Got the half power light to come on under normal mode. It came on at 6500 rpm after a loud hiss. Will be working on it tonight to confirm. Ideas on confirmation or other things to look for?

 

Sounds about right... Same issue I had except it was due to an aftermarket Diverter Valve. If yours is stock, dealer should cover under warranty. If not the part cost about $65ish, and is a breeze to replace. Good luck.

 

I have 80K miles on it, what would it fall under for warranty replacement?

Nvm, reread the post. Had a heat induced blond moment.

 

Ms. Frizzle is at the dealership, BMW/MINI of The Woodlands in Houston, TX, getting some open recalls taken care of. While that is being done, I asked them to go ahead and replace the diverter valve. When I get her back she should have the new turbo heatshield w/ oil line shield, new timing chain/tensioner, and a new diverter valve. As far as cost, they are to call me sometime today with labor cost for the valve.

I was treated well, and given a loaner, 2014 MCS Convertible w/automatic. I was less than 15 minutes away when I already missed my 07 MCS. Some changes I do like, most I do not. The seats are better support, but less comfortable for long drives. The automatic in non-sport is sluggish. Center stack volume control moved. The steering is sloppy in non-sport. As far as the good: The under-hood is cleaner. They moved the low side AC port next to the drivers headlight. Speed stays on the upper display of the tach. Cruise control appears to be smoother.

I will update again when I hear some news. I want to thank Roxspin72 for pointing me towards the diverter valve. I really do hope this is it and I can get back to enjoying my magic school bus.

 

NP. Hope all works out well. If you are looking for an upgrade from that brand new DV, look into the ALTA DV uprated spring, I installed it in mine, and works like a charm. Maintains boost level, and increases response.

 

So a delayed update:

The dealer fixed all recall items listed on the car. Including timing chain!! (No more rattle!!) Then wanted $120 for the part, $210 for labor. Labor that could have been done when the car was in service mode for other items. Quote was requested before they do any work on the Mini, but was not looked into or provided until after the recall work was complete. Unless I have to, no other work will be done at this particular dealer again.

The plus side: The new diverter valve will be delivered to my home in the next 45min. Then I will replace it tomorrow night and finally confirm that this was the issue and that the dealer was full of themselves trying to sell me a new turbo. If I'm going to pay $2K for a new turbo, it will be a upgraded unit.

Any help in how to actually get my hands in there to do the swap would be greatly appreciated.

 

Its really not too bad. Just move the coolant reservoir out of the way and undo the 3 allen head screws. Reverse for install. Tight and the back screw is tricky. Just take your time, it'll be easy. It takes me 15 min to remove and install, tops.

 

Mr. Rauscher. Can't wait to hear your results. I have the same symptoms with my JCW. When I accelerate hard enough, I get the yellow half engine light, but the car throws NO CELs. I'm also getting NO boost (ScanGauge). The engine never goes into "Limp" mode, just has no boost. I hope a new diverter solves both of our problems.

 

With my faulty diverter issue I could hear a harmonic noise from the inlet tube area at idle. It was vacuum harmonica noise from the torn diaphragm in the diverter valve. Give a listen, perhaps remove the inlet tube and listen in there. GL

 

I can tell you, Yakatak, that the diverter valve is it. When I use sport mode, windows down, radio off, and drive down the back alley in my neighborhood, with fences on both sides, at just over 4K RPM I hear, while still accelerating, the diverter valve dump to atmosphere. Then no boost is registered at all on my reader (BT scanner to android device). It seems to fail in the open position rather than stay closed. In theory (mine) this helps to keep the turbo fins from damage, but also keeps the line open for no pressure.

I will attempt to get it changed tonight after work and report back. At $65 (eBay) it is one of those parts that if it is even suspected now, it will be replaced. Going to try and get a GFB DV+ later on though.

 

Haha, 80K on my 07 MCS and I had the same issue pop up this weekend. Figured out it was the diverter valve due to the blow off noise sounding like a small bird getting sucked into the engine. Apparently the OEM valves only last about 80K.

Got the upgraded spring from Alta to install in the new OEM valve. Anyone have any experience changing the springs? is there much of a difference?

 

Yeah, mine started at 81,034 on the odometer. What a way to sell people useless turbo replacements eh?

 

Big difference. Night and day even over the Forge DV. Like I said not sure if my Forge unit was defective from start, but after reinstalling stock DV w/Alta spring, I will never look back. Worth the $25ish w/shipping and 1/2 hour install time👍

 

Well....Fixed mine today and it was not the diverter valve. I was playing with the vacuum lines at the turbo to see if I could diagnose a failed diverter valve diaphragm, without actually taking it off. I found that I had no vacuum at the wastegate dashpot. The wastegate is normally-closed by vacuum when the engine is not in a over-boost mode. So...no vacuum...the waste gate is open and...no boost. Followed the vac line back (Braille method from below) and, sure enough, the hose had popped off of its nipple on the vacuum box. All is well...zoom...zoom. I'm still surprised that this condition would bring up the yellow half-engine light but no CEL. I've been searching the forums all week and never saw this mentioned as a possible cause for a no boost condition. Nothing like being a pioneer. I will be putting in the ALTA spring.

 

New diverter valve in. Omg!!! Ms. Frizzle is so happy to be holding boost again! It took about an hour to do, I'm 6'4" working on a lowered MCS with no ramps. Back is killing me. Attached is a comparison of the new vs what I took off.

 

The reason you have no code is because it's a mini specific code. You will not read that with a Scangauge II. You need something like BMWhat software on a smartphone or bravarian technic software and hardware.

 

Man that would suck. I'm only a wee lad of 5'6" and it can suck for me to bend over the little car after a while. I can't imagine how it is for you, who is nearly a foot taller than I!

 

I DO have another scanner that shows Mini specific codes. No codes were thrown...honest.