mods:

stock twins
V mount
exhaust (with high flow cat)
stock recirc valves
knightsport tuned ecu


problems:

wont boost over .5 bar

symptoms:

when boosting in any gear it sounds like there is a big boost leak but im 90% sure its coming from one of the recirc valves

car pulls hard once the secondary turbo kicks in..just sounds like the primary is leaking

i have a boost controller hooked up, HKS EVC-R , makes no difference, it actually boosts higher w/o it, just better low end throttle responce when it is on



any ideas? a solenoid or vaccume line? lol

 

TAG - I have the exact same problem - been trying to solve this for a long time.

 

so does one of my neighbors actually. its a big mystery...lol

 

I was trying to compile some data about this. The only things I could think of are as follows:

1. Exhaust leak before the turbos - gasket bad on manifold to turbos primary side (leaks out primary exhaust to atmosphere thus not allowing the primary to spool or hold boost.) (have not inspected this)
2. Leak in an intercooler coupler (this may be a contributer but probably not the culprit)
3. Leak in the larger hoses coming off the y-pipe that go to the BOV and CRV (I've checked these several times)
4. Faulty BOV (currently have this swapped with another CRV for testing - so this was not the issue)
5. Faulty CCV or CCV screw needs adjusting (door could be open or slightly adjar robbing primary boost pressure and venting to atmosphere) (I've checked the screw adjustment and watched it's operation during the KOKO test)
6. Faulty solenoid creating leak or vac hose is leaking somewhere in rats nest that connects to UIM (I've been all through this - everything with the vac hoses is where it should be, however I have not bake tested the solenoids for operation yet)
7. Faulty TCA or TCA needs adjustment (door could be open robbing primary boost pressure for the secondary and venting out the CRV before 4500rpm) (I've checked the screw adjustment on this, but could not get it to perform on the KOKO - will try this again after I take a short drive to build some boost.)

The facts:

1. The specific sound of the leak sounds like it is a large leak.
2. It sounds like it comes from the turbo side of the engine.
3. When you press the gas it struggles to build boost and will only reach 5psi on WOT but feels like it's hardly getting any boost at all.
4. At 4500 RPM the secondary immedeately kicks in and boost goes up to 11psi and then drops to 9ish and holds till redline

Other issues - may be related - may not be

1. My idle is around 1500rpm when cold, drops to 1100 warmed up
2. Upon deceleration my revs will hold around 2k until I come to a complete stop, then drop to 1100
3. When the engine is cold, I sometimes see a hunting idle for a short period of time.

 

Make sure all your turbo control and wastegate actuator rods are secured in place on the arm pins. The little circlips that keep them in place rust and thin down quite a bit, which eventually causes them to fall off after a while.

 

I had this problem. I triple-checked the return hoses, but it wasn't until I removed and bent the hoses did I find the leak.

 

check turbo control actuator solenoids.

 

hahhh.. foudn the problem, first i blocked off both the recirv valves, and there was still no compressor surge, and we could hear air coming from somwhere.. ends up the coupling that goes to the Y pipe for the turbos had a pretty damn decent sized hole in it! put a silicone coupler on , put everything back together n now its fast as **** !

 

i spy a cracked coupling..

 

glad to hear it man -

I have a enfini y-pipe - this doesn't help me

 

You've had all those mods and have not upgraded to an efini Y pipe? I think that was one of the first aftermarket changes I made to the car and I'm one of the slowest to make such mods. Had to be 6 to 8 years ago now. Get rid of that weak link in the IC plumbing.

By the way, rarely do you have failure in the stock CCV or BCV. Mazda gave us a pretty good product there.