Hi folks a little problem maybe you could help with.

My R56 is Evolve Stage 2 tuned with Forge FMIC, Forge BOV, Evolve de cat down pipe.

Recently I start the car, drive for a few minutes all normal. I put my foot down, lovely acceleration, no probs. After one or two playful WOT I loose boost. If I turn off the car, my boost returns...HELP! Please!

 

check engine light on? Check the pending trouble codes too. If you double tap the throttle really quick where the old OEM tune would do the "overboost" function sometimes the Evolve tune will back off to like 3-4 psi. Once I banned this technique from my habits I never had a problem again. However, it sounds like you have something else brewing.

 

No cel, no codes. No boost! Thought it was heat related but happens in the rain and boost returns for a short time after i turn the engine off.

 

Sounds like the ECU is going into Soft Limp Mode, where it restricts the amount of boost to protect the engine from wrecking itself.

What scanner are you using? Is it an approved MINI-protocol scanner like a Bavarian Technic unit?
If the ECU is going into any sort of protective mode, there will be associated fault code for such.

- Erik

 

What scanner are you using? Is it an approved MINI-protocol scanner like a Bavarian Technic unit?
If the ECU is going into any sort of protective mode, there will be associated fault code for such.

- Erik[/QUOTE]

Cheers Erik

I used my scangauge and then my mechanic friend used a proper BMW unit, or at least one with graphs and graphics on a big screen! No codes.

Its not really limp mode as the car still runs, just boost limited to about 5psi...maybe that is limp mode. I can still get speed up, it just takes longer!

 

Oh yeah, that's Limp Mode. Enough to power the car home, but safe enough to keep any damage from occurring.

- Erik

 

The car is over loading. Do you have a boost guage? If you can check I would bet your htting the 22.5 limit. Call evolve and see what they can do. I have noticed that ambient temps play a pretty big role in this issue. As your IAT's go up so does the amount of boost. At 60F you may not have any problems but at 85F it will over load.

 

The exact same thing happened to me and it turned out to be the diverter valve on the turbo. I would start the car and it wouln't throw a CEL or anything and if I didn't drive to hard everything would seem normal, but if I stepped on it a couple of times I would loose boost.

 

KarmaMSP...SPOT ON! Thanks!

Problem solved. Seems it was a mis fitted inverter valve. I was getting some boost but overboost would send ECU into limp mode. Thanks to all for your comments.