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) when the throttle is let off.

Can someone help me source this problem ? I've tried the majority of troubleshooting procedures on the autosportracetech site , and I'm stumped. Some say I need new spark plugs ? But I don't know, maybe, it's worth a try.

 

It is not your spark plugs. See if the clips that connects the actuators are on there. Also, for kicks try boosting to 5k rpm then let off and step on it again immediately. If the second turbo comes on, then its a "rats nest issue".

thewird

 

Check the vacuum and pressure line going to the Turbo Control Actuator, it could also be the Actuator itself....

 

All clips are intact for both vacuum and pressure hoses ; I reinforced the hose with tie-wrap. I found that the pressure hose wasn't fully in, there was about 1 cm more to go in but I don't think that was the problem because the state the hose was in - is enough to receive boost pressure.

I'm gonna check if the hoses goes where its suppose to be - thank god we have the rats-nest diagram.

 

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.

 

just store it
we will figure sumthing out next year

 

I had same issue for about 7 month hope it gave my engine nice break in time, my 3rd woudnt boost all the way and lost power but 1, 2nd was ok , after new Greddy pro racing plugs it boosted immediately and after couple street driving it was running very nice, Ryuji dont worry anees will help you

 

I don't think its the same issue.

thewird

 

I can not understand how plugs would make a whooshing sound.

https://www.rx7club.com/showthread.p...ight=secondary

https://www.rx7club.com/showthread.p...ight=secondary

https://www.rx7club.com/showthread.p...ight=secondary

https://www.rx7club.com/showthread.p...ight=secondary

Doubt this one - although that reminds me. Marco did you fix the issue with the car you had? I do not remember who's it was but you said it got boost ok in some gears, and not others....
https://www.rx7club.com/showthread.p...ight=secondary

Maybe this one
https://www.rx7club.com/showthread.p...ight=secondary

 

It was the boost FJO boost controller. Put a Spec II on it and problem solved.

thewird

 

ya i will help you .. but i think u are going to mazd33s today rite!!