Hey guys, I'm having trouble sourcing what seems to be a boost leak during the operation of the Secondary turbos [4500 rpm]. I've already conducted the autosportracetech boost test and I found that my Primary turbos are working fine -- boosts up to 10 PSI no problem -- but I've noticed that when I pass the 4500 RPM mark, right when the second turbos are suppose to kick in, the boost gradually goes down and nets less than 5PSI; it is also accompanied by loud whoosh (no, not the BOV)that sounds like it's coming from the passenger side when the throttle is let off --btw my FD is a RHD. I've uploaded the sound it makes when I let off the throttle (http://www.megaupload.com/?d=5XE0YM8I)
You can hear the described whoosh sound at 0:02.

Can someone help me source this problem ? I've tried the majority of troubleshooting procedures on the autosportracetech site , and I'm stumped.

 

if that sound really is after letting off the throttle, then that is your BOV.

 

It's not the BOV, I meant the sound after the PSHH; there is a sound after that kinda sounds like a goose, it's hard to explain

 

Im having the same problem, check out this thread https://www.rx7club.com/showthread.p...econdary+boost

 

What Dale described seems to be what exactly my problem is. Have they come with the solution yet ?

 

as far as I can tell it is the charge control actuator not working properly. either the solenoid controlling it is not functioning properly or the charge control valve its self is not functioning properly.

 

yea for a while I was getting no boost in my primary turbo but I got that working by replacing the whole CCA from the Y-pipe even though the other one seemed to look like it was working fine. Now for some reason I get no boost for my secondary turbo. However, after a week or so of searching I just tested all my actuators again and replaced the precontrol solenoid and the wastegate solenoid today, just because, and now when I drove it I still get 10 to 11psi but when I hit close to 4500rpm the car jerks a little and my psi jumpes to 14.5psi and I let off the gas quickly because I didnt know what was going on... I had to leave it like that today because I had to go to work but I dont know if that was just a boost spike or what because I didnt continue after it hit that high of a psi because I didnt want to break anything.

 

I'll check it out tomorrow. My car is a RHD and the CCA is located on the driver side; when I hear that weird sound when the throttle is let off, you can hear it coming from the passenger side : S , it's worth a try though. Let me know how yours is doing afterwards