Today I went to the dyno to get my car mapped with BNR.
I have used the simplified seq vacume diagram I found here and have been very carefull to install and make sure everything was good connected.

But today at the dyno we found out that only the secondary turbo worked.
At about 3800-4000rpm the boost from sec.turbo came as lightning and teh prespool system work as supposed to.
But before 3800 rpm there were no boost from primary turbo.
Right before sec.turbo kicks we only get 0,15 bar pressure on the primary.
I have checked that the primary turbo spinns and make air pressure ,but not so strong,we could hold the pressure back from the ypipe with are hands when the 0.15 bar pressure came from primary turbo.
We have cheked all the vacume lines. And everything seams to be good.
We think that the precontroll actuator could be stuck or not work.(maby most of the exhaust is routed away from the primary turbo.
This I will check next week.
I have a feeling that the turbocontrol have something to do with the problem as well.

When the turbo 2 kick in at 4000rpm we get 0.6bar... before this as metion before nothing happens.

Anyone that has something to replay to this that could help me?

 

Is the stock prv hooked up right?

 

Whats a PVR?
I haveconnected the vacume and boostcontroller like in version 1 in this link: https://www.rx7club.com/showthread.p...simplified+seq

 

On the last car that I had in the shop with the same problem that you are describing, the issue was a faulty turbo control solenoid.

 

okok..

But I tought that the primary turbo dident need any solenoid controll up to 7 psi because of the spring in the actuator,isent this right? or am I thinking wrong?
If this is so I will change the turbocontroll solenoid and se what happens,I should feel a powerboost at low rpm I guess.

 

Both turbo control solenoids need to work to allow the turbo control actuator to function correctly. In this case it was allowing the exhaust flow to the rear turbo, when it should have been diverting all flow to the front. This reduced the primary boost to 0, then it would jump to 14psi after transition.

Do you have the vacuum system simplified or is it still all stock?

 

I have used version 1 in this link: https://www.rx7club.com/showthread.ph...simplified+se
I have boostcontroller connected and the solenoid J in the cacume diagram as followed.

 

It is my understanding that the turbo control system cannot physically stop flow to the primary turbo. So it would have been behaving as a non-sequential system. Which is exactly what this sounds like.

 

That is correct, it can not stop or interupt the flow. However in the instance that I outlined above, the turbos were set up as sequential and the TCS was not operating the TCA correctly. This allowed the turbos to function similar to NS, with exception to the fact that the CRV and CRA were both functioning as sequential. This diverted the exhaust flow to such a great extent that it yielded no primary boost.

We know for a fact that is this case it was a faulty TCS, as we changed out each solenoid, the WG and PC actuators and the TCA individually, until the problem was resolved.

This resulted in 0 boost on primary, with full boost immediately after 4500rpm.

 

Do this means that it could be the acturator is stuck or dont work and maby the turbocontrol solenoid is bad... And this is the only two options it could be.
Because I have check that the primary turbo itself works only with to little ecshaust routed to it.
ps!!! the bnr twins is set up for seqensial set up right from bnr it self.

 

That makes perfect sense, as the charge relief valve would be dumping all the boost from both turbo until it is closed for when the secondary comes online?

 

I have the same issue with my car. Feels like more lag then single turbo
I think if it were the charge relief valve not closing, you would definitely hear the boost dumping to atmosphere.

 

The primary turbo is not dumping the pressure trough the charge relife since the charge relife is connected to the secondary turbo and not the primary.The other valve in the ypipe is also working fine since we have boost coming trough when we take of the ic piping,its just not strong enough( only 0,15 bar at the most,and if we take an close the pipe with are hands it starts srugling right away to make pressure.

 

Is the flapped in the y pipe not closing? That would allow primary boost to escape through the crv.

 

When you turn the key to the on position does the Turbo Control Actuator on the manifold move?

We also recently had a car in the shop, where the TCA was mounted upside down. This reversed the vacuum and pressure lines. This car also had very little primary boost.

Here is a dyno sheet from the car I previously posted about. The first run shows a functioning Turbo Control Solenoid, the next two (lower HP) with the bad solenoid. You can see where the car is making less than 100 whp until after transition.

 

I dont think the tca moves at all when you move the key!!!
I guess you guys have right about my problems,I just dont understand completely how this system works.
Ill come back with more updates next week,I cant fix the problem before,because im helping a friend with something.

 

Thanks for all the answers.
Can anyone tell me what colour it shoud be on the solenoidplug to the turbo control solenoid for my rx7 94 mod j-spec.
I think my problem might be here since all the other vacum system work ant the prespool ect works fine it has to be the TCA that doesent work like it should because of the TCS is not connected to right plug.

 

There are two Turbo Control Solenoids. One that controls the pressure side of the TCA, which looks like all the other solenoids and is the tan connector. The other one was mounted on top of the ACV, which has a connector like the WG & PC solenoids, this controls the vacuum side of the TCA.

Use a vacuum pump, apply vacuum to the nipple in the center of the TCA, it should move

 

Ok I connected the tan plug to the (E) turbocontroll solenoid.
But the tan plug was connected to another solenoid. I now whant to know what colour it is on the other solenoids I have.. I dont fix primary boost and disable something else.
Anyway, now I got 0,55 bar boost on primary turbo when I connected the tan plug to the TCS

 

H is Black
F is White

You are not using any of the others unless you have the FPR still which is A/orange

 

okok.. Then the carge controll have never worked ither,because the tan plug was connected to this one.
OKOK:: Than I thnik aveything is up and go,Thanks for all the help guys

 

im having this same problem on not getting any boost from my primary turbo on my JDM motor that i just put in and i changed all the vacume hoses under the upper manifold with silicone hoses and then ziptying them all, checked all the solenoid valves to see if they are cracked or broken, replaced the Actuator (turbo precontrol) and the vacume hoses conected to it, i also checked if the actuator (charge control) open and closed when the car was running and turned off (the flap shuts when the car is on at idle and opens when the car is off). Also, i hear a lot of air coming out until it hits somewhere over 3000rpm then you can feel/hear boost builing up for the secondary turbo and then at 4500rpm i get my fool boost for my second turbo and it seems fine after that. basicly feels like a fat lag till 4500rpm. also i checked both turbos to see if they spin good and they do... what do i do now??? put a for sale sign on it???

 

You describe the problems you have to be just the same that I had.
For me it was only the solenoid plug that was in the wrong solenoid
Check again over your solenoidplugs.
PS!!! change the white and tan colourd plugs with the solenoids and see if it helps

 

what is the color order for the solenoid plugs? starting from the front isn't it black on top of green then white, tan, gray, blue, and orange.
and i read in a thread that if you want to check if your solenoid works then connect a 12V battery to it and if you hear a click then its working, is this true?
also when i was looking at my vacume hoses i noticed that there were two hoses that where "flat" (like when you suck on a closed end straw and it becomes flat) one conneced to the top of the H solenoid valve (charge relief) and one that connects to the end of the F solenoid valve (charge control). when i popped the flat hose conected to the top of the H solenoid i heard air getting sucked into the solenoid... whts going on there and is that supposed to happen?

 

yes you can hear a click when you connect 12 v to the solenoids,But you dont need to to that now.
The colours of the solenoids is:

H is Black
F is White

Try this first,because some off the solenoids that controll the twins do the same things and open closes at the same time.
Make sure the f and h solenoid is right connected first,and make sure all you vacume line that is pressed flat is fixed.