Hi everyone. I wanted to make a post regarding a Limp mode light that came on recently in hope it may help troubleshoot another individuals who has similar conditions.
I have a 2007 R56 Mini Cooper S Turbo. I installed a OPL (ebay) Intercooler and was smashing on the throttle right after I installed it on the highway.

Diaphram unit from Diverter Valve destroyed

Another view of the damaged diaphram.

At high boost ( Revving high 2nd-3rd gear) the light came on and immediately had reduced engine power....BUT only for a short bit power appeared to return to normal but the light remained ON.
After further inspection, I found the boost blew out diaphram on the diverter valve.
It is my suspicion that the new intercooler having a larger volume was storing up a higher volume of boost pressure and thus upon attempt to divert boost it blew it out.
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If it's the original OE diverter valve then if has done good for ~13 years of use. The original ones have the exact known problem you've listed above.

 

It was probably on its way out already, then when you started beating on it with the new intercooler, it let go.

This is the newer version:
https://www.ecstuning.com/b-pierburg...658636606~pie/
https://www.ecstuning.com/b-genuine-...e/11658636606/

Or, you could get an upgrade:
https://www.ecstuning.com/b-turbosma...0223-1293~tsm/

 

+1^^ njaremka

 

Damn, she held on as long as she could. Get the updated DV and the alta boost spring, you should be good to go. Me personally, im running the updated DV, alta boost spring and forgery spacer with no issues. i am running a g+ intercooler as well.

 

Lol I bought these below it's a generic BOV copy of the forge I guess and same with the adapter plate. Would the spring and all these together work? Can someone give a sol9d explanation how all these work in congruence in regards to boost? Thanks!

 

Yea, the adapters are simple. I like the forge ones as they are made very well. Those other ones i have no clue if they function the same or are good or what spring they run. Who knows? I run a forge BOV upgraded unit and its made very well and no issues. The forge stuff is quality .

 

You purchased the blow off valve AND a blow off plate? I'm not sure those are going to work together....

You cannot use the Alta spring in that Ebay valve. The Alta spring will only work in the OEM style valve.

I also have a Forge valve on my car.

 

I like the Forge DV’s, I have a GFB DV+ that is great as well. Even with the newer style diverter you should be fine, mine worked just fine with the Alta spring @ 22psi.

 

Yes. I understand. Question... so the adapter just creates more space or increases volume between... idk.. so what's it do?

 

The adapter is meant to basically turn a diverter valve into an atmospheric blow off valve. Instead or recirculating the excess boost back into the intake, it vents to the atmosphere. They sound really neat, but it’s possible it could throw a CEL too. I’m not sure if they meter the airflow enough for that or not, Ive been told that they both work fine and throw a CEL. I guess you just have to see what happens.
If the valve you purchased is an atmospheric blow-off valve, there’s no point in using the plate at all since they sort of achieve the same purpose.
that one, like the Forge is vacuum actuated, so you will need to run the lines for it, as the factory DV is actuated by the ECU. The GFB DV+ uses the factory solenoid but replaces all the plastic bits that broke on yours and the piston with metal parts.
The aftermarket diverters and BOV’s usually have a few different spring options to fine tune it’s operation with your boost levels. If you are not tuned, the normal spring should be fine

 

Thanks for your expertise. I do not have a tune, so I am just going to bolt on this knockoff Forge Blow Off Valve and see what goes on. Do the Forge BOV or any for that matter have a possibility of setting of Check Engine Light?

 

I’ve never used one of the eBay finds, but the Forge and others like it usually don’t cause any issues. The only thing may be the air metering issue. If it’s an atmospheric BOV it could possibly throw a CEL, but if it’s a diverter, there should be no issues at all. The BOV’s seem sort of hit or miss, but I know a ton of guys running them just fine too
Good luck, and let us know how it goes!

 

Indeed I will!

 

yeah you dont need both, but i have the spacer like the one that you have in the bottom pics, i paid 9 bucks shipped not 18. No CEL with the spacer, updated DV, and Alta boost spring. Got to drive into work today and was hitting 15.5 lbs of boost no issue and triple digits tend to sneak up real quick

 

Man that's awesome! Which creates a better throttle response the spring upgrade, adapter, or BOV?

 

For throttle response and quick spool up Im sure its a combo of the spring and DV, turbo muffler delete, g+ intercooler, and forge noise maker delete. The adapter is just purely for the psst sound when coming out of boost.

 

When you say Diverter Valve how does a blow off valve differ?

 

Basically they are same thing. I just think of BOV as one of the big ones you see on intake.

 

Diverter valve recirculates to the turbo inlet, blow off valve vents outside the intake.

The GFB DV+ is supposed to increase throttle response.

 

So it vents the boost that the ecu allows or the cooling side of the turbo outside? Does it technically mean that there could be less boost or is it set to a standard psi and then releases anything over that?

 

You have what is going to be a replacement, that will be loud. YouTube search forge divertor valve on you tube for Mini Cooper, might need to use blow off valve, it’s been awhile since I have watched one.

 

Boost is only made when you are on the throttle. The ECU controls the amount of boost with the wastegate.

The diverter valve controls the release of boost when you let off the throttle faster than it can be controlled by the wastegate. (Picture going full throttle, then immediately lifting you foot fast off the throttle pedal) In this case, the diverter valve opens, and any boost built by the turbo is either recirculated back to the intake, or vented out to the air.

 

When using the word Diverter, this means the boost is diverted to the engine cylinders again?

 

Also, what is the purpose of the MAP adaptor in these BOV/Diverter kits?