Hi,I write from Italy.
In these days I am working on my best friend Lancer EVO VII, ECUID 99860002.The setup is
Exh : Tomei elbow and downpipe,decat,and Kakimoto cat-back.
Other : HKS in box filter, solenoid pill removed, tomei recirculated BOV,standard but new WG actuator,265lph SARD fuel pump.Ah, and a stainless steel turbo to MAF intake.
I have temporary mounted an LM-1 wb and a big professional boost gauge.
This is not my first evo with ecuflash, I have done many evos, but I haven’t ever seen an issue like this :
The first day all seems to be , with WGDC set to 100% I can have 24psi peak and 21psi to redline, so I don’t need to change actuator pill.
I decide to work on BCLO,BDEL,base WGDC and boost limit to have 21,5psi peak,20psi@7000 and 19psi to redline .The AFR is a little on the rich side and the knock is low,2 or 3 events.
The second day after that I have warmed the engine,I go to do the first day datalog. But at 5500-6000rpm the boost drop to 16psi and I can hear a little air leak from somewhere. This event appear in every gear at 5500 rpm, below 5500 all is OK. The first strange thing is that the AFR above 5500 rpm doesn’t becomes very rich, as I would expect to happen if there is a boost leak!!!
I have the boost cut set to 315 and 3000ms,so It isn’t a boost cut. All the tubes of the boost gauge are ok. I have put a cap on the air source for the SAS,so it can’t be a defective SAS valve (that in any case is not active in ecuflash).
The VERY STRANGE thing is that when this boost leak appear,the 2byte load and 2byte airflow don’t go down,but the ignition timing go up as if the ecu is really reading from low load cells (and I have a bit of knock,from 4 to 8 events).This is VERY strange!
Have someone hear of anything like this?

 

Can it be the EGR valve that above 5500rpm opens under the pressure of exhaust gas?

 

Here it is a screenshot of a 4th gear pull.



The map was a stock one with 2bLoad enabled,a bit less timing up to top and a bit less base WGDC (and increased boost cut thresholds),but the issue is still present!!!
You can see that at 6000rpm the 2bload increase but the IPW decrease!It is the moment when I can hear the air leak,and the boost go down to 16psi.The AFR is not showed,but I can guarantee that don't change.

Why the 2b load increase??

What can cause this?An EGR or WG leak?

 

SOLVED!
It isn't a boost leak or an EGR leak!
It was an air infiltration on the intake,between MAF and compressor.

BUT why the 2bLoad increase??