As the title states, and photo attached. If I have both chambers to the charge control actuator connected, I only get primary boost. If I disconnect chamber B, it's VERY laggy, but I can hear and feel the secondary kick on. Chamber A routes to solenoid F, but I'm unsure if it's a failure of the solenoid or my vacuum routing.

 

I have to ask if you currently have that nipple on the actuator open like that. If so, it would be best to start with routing that properly before any further troubleshooting. It shows in the vacuum diagram and also in random pictures in a Google search

 

I specifically addressed this. With that line disconnected, I see secondary operation. I even included the diagram from the FSM.

 

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Seems my eyes move faster than my brain. We ran into a similar issue once before and turns out the actuator arm was sticking during actuation. We found this by removing the y pipe and testing it with a vacuum/pressure pump. Replaced it with one that didn't do that and the issue went away.

we were troubleshooting random sequential functionality operation. Turns out the actuator would randomly stick open sometimes. We troubleshot it on the dyno so we were able to just look at it and it happened to not move one of the times we were watching.

Without a dyno, its difficult to watch the sequential system work to determine whether or not it's a solenoid or an actuator issue in real time. To troubleshoot the solenoids you obviously have to take them out. We have a video on our YouTube page on how to test them.

I would suggest testing all the actuators first and then moving on to the solenoids. The actuators are easy to test once you find a way to access them to apply pressure or vacuum.

99% of the time, its a solenoid or vacuum line issue. Although only once twice have we seen an actuator be a problem. The first one above and the second was a frozen pre control. We applied air to it, it made a loud cracking sound like a branch breaking and then it worked like normal and has ever since.

 

I do have a vac/pressure pump, though it'd be odd the actuator works when pressure isn't applied to chamber B. I'll give it a shot anyway.

 

You should be able to test with IGN on/off. CCA actuator key off should be fully extended and key on should be fully retracted. I just tested on my car and the retract distance is pretty apparent. If you key on and the arm does not move then you know your issue is either the actuator itself or it's vacuum side.

That's so odd that you get some function with the pressure side disconnected and no function at all with it plumbed in. You would think it would at least not make a difference.

Maybe you've got some gunk blocking that port that supplies B with pressure? Or maybe when you plumb it in the silicone hose gets kinked or something and it seals chamber B.

EDIT: OK I had to brush up on rats nest functionality. Here's my understanding of the situation

CCA controls the little flapper door between primary and secondary. When the rod is out, the shutter valve is open, both turbos are connected to intake. When the rod is retracted/in, the shutter valve is closed, the 2ndary turbo is no longer connected to intake.

The way this operates is through pressure supplied to chamber B and solenoid input supplied to chamber A.

Pressure supplied to chamber B is always acting to keep the CCA valve closed, and separating the 2ndary turbo from the intake.

Solenoid input supplied to chamber A is what moves the actuator. This solenoid gets both vacuum and pressure, and switches between the two supplied to chamber A. When vacuum is supplied, it assists the chamber B pressure and forces the CCA closed. When the solenoid switches and pressure is applied to chamber A, then it cancels the pressure in chamber B and allows the valve to open.

I believe this is why you're seeing better laggier performance with chamber B disconnected, without pressure in chamber B then the solenoid has less to "fight against" when supplying chamber A. When vacuum is applied to chamber A and atmosphere is in chamber B, then a small amount of boost is allowed to leave the intake through the 2ndary turbo tract. When you go into twin turbo operation, pressure applied to chamber A has no pressure in chamber B to fight against, and allows the 2ndary turbo boost to be supplied.

When you plug your chamber B back in, the pressure supplied to it is too strong for your solenoid supply to work against, and it shuts the valve closed completely.



This image was stolen from another thread but the Green is the pressure supply to the solenoid, the Blue is the vacuum supply, and whichever pressure or vacuum the solenoid is selecting travels through the Red to affect the CCA.
If you don't want to start taking bits off the car, you can test the bits of rats nest routing on the car for leaks.
With IGN on, ENG off, pop the Green line off the 2ndary turbo elbow and apply pressure. If it can hold pressure then your solenoid is not switching properly. If it loses pressure over time (I think this is what you'll run into) then you've got either a leaky pressure circuit or a leaky solenoid valve.
With IGN off, pop the Blue line off the UIM, pull a vacuum into it. If it's losing vacuum then you've either got a leaky vacuum circuit or a leaky solenoid.

 

A minor, but likely irrelevant note, the twins are Series 8 examples.

Tests done:
Applied pressure and vac directly to chamber A, door moves. Feels sluggish.
IGN off, -.25bar on vac circuit via hose from UIM, pre check valve. Held for 5 min.
IGN on, 1bar on pressure circuit via port on secondary output. Held 5 min.

So if I am reading correctly, test 3 (IGN on, pressure holding) means my solenoid F is not switching correctly. Coupled with a slow CCA, means the valve would never open in any reasonable time frame. Disconnecting the pressure source on B means less resistance for A to apply to push the valve open.

Or if I'm reading wrong its just a super slow CCA. Is there any way to regrease it?

 

I don't know if there is a way to regrease it. I have heard that there are so many people ditching twins that you could likely find a working replacement for the pipe that has the CCA on it in the marketplace for cheap. The hardest part of taking it off is getting the intake pipe off that turbo, two nuts on the backside. Though, if it moves at all I would gather it's probably OK?

That's a good sign that both sides of that solenoid are holding pressure/vac. With everything put together, did the actuator change position with key on? It should've retracted.

Next step is probably to take the solenoid out and check it according to the FSM. See this thread.



There was another thread where someone was having transition boost problems, also with the CCA. It ended up being his PowerFC wasn't supplying enough voltage at the connector to the solenoid. That would be worth checking as well. IGN on it should see 12V.

 

I believe it may just be the CCA. When applying 1bar to chamber B, it bleeds off pretty quickly. So I believe the bushing keeping things sealed around the rod is shot. Though that doesn't quite explain why the door sticks shut when B is connected.

 

Hrmm. That's a strange one.

Based on your symptoms I don't believe a failure in chamber B would lead to the symptoms you describe, but let's rule out the CCA and related rats nest entirely.

Can you retest your CCA in isolation? When you supply vacuum or pressure to chamber A, additionally supply 0.8bar pressure to chamber B to simulate primary boost.
If you've only got one pressure tester, when you pressurize both chamber B and chamber A, use the same tester and tee into both, it should be fine.
Pressurize both chamber B and chamber A with equal pressure.

Pressure in B + Vacuum in A = CCA arm in
Pressure in B + Pressure in A = CCA arm out

Before looking for a replacement for the CCA, let's totally rule out the solenoid, rats nest, and CPU signal by simulating 2ndary boost mode.
I am recovering from a food coma, so apologies if there is a simpler way to diagnose this.

Apply 0.8bar of pressure directly chamber B, to simulate primary boost pressure
Additionally, apply 0.8bar of pressure to the hose from the 2ndary turbo pipe, like you did before.
If you've only got one pressure tester, you can tee both lines together and pressurize them with the same tool.


Chamber B will always see the 0.8 bar of pressure you are applying.

With IGN ON, engine OFF, the solenoid should be directing vacuum to chamber A, verify that the CCA arm has retracted.
The 0.8 bar of pressure applied to the 2ndary turbo hose should be halted at the solenoid, the whole system should hold pressure, as you've verified before.

With IGN OFF, engine OFF, the solenoid should be directing your supplied pressure to chamber A, verify that the CCA arm has extended out.
The system should hold pressure.

Result
If the CCA is behaving in any way other than intended, you've isolated the CCA circuit as the culprit.

If the CCA itself passed the test at the top of this post, but the whole system did not pass the test with the rats nest involved, then you have isolated the problem to the rats nest, or the solenoid, or the solenoid signal. Since you've already verified no leaks last time, this is a strong sign your solenoid is faulty or it is receiving faulty directions from the ECU.

If all tests return OK, then your CCA is behaving as intended, and your boost should be normal. If it isn't, you've got problems somewhere else besides your CCA.

In such a scenario, the only thing I could possibly think of is that your charge relief valve might be stuck open.
The charge relief dumps your secondary pre-spool back into your air cleaner, and closes after transition. If it is stuck open, then the pressure supply to chamber A would be reduced, and that would explain why the CCA is stuck closed if everything else is still working.

 

Put -.5bar into the vac side, using the check valve to keep it there.

1bar applied to B and Pressure circuit. ~10sec to fall to zero (though the CCA bushing). Rod is fully retracted with key on.


1bar applied to B And pressure circuit. Same result. Arm moves out without vac present.

Seeing as I validated the pressure circuit at 1bar. I believe directing primary pressure to B as normal leads to an odd case where the valve is fluttering between open/closed, so I am unable to balance the turbos. This leads to the secondary unable to build the pressure to open the exhaust door and receive full flow. With B disconnected and at atmo, the door works according to A's pressure/vac condition, albiet with no regard for the 'balancing' act, meaning the valve may open prematurely, but enough boost is created to operate the exh door fully.

 

The results of your test lead me to believe the CCA solenoid, CCA actuator, and your rats nest are behaving well and are not your problem.
There is a spring in Chamber A, so if Chamber B pressure = Chamber A pressure then the spring should be the only net positive pressure, and the valve should be stuck open, rather than fluttering.

Going back to your concern about the pressure leaking out of chamber B, I don't believe it is the cause of this problem with boost not coming on but it probably is some kind of problem and should probably be replaced.

If I am interpreting your words correctly, I think you are on the right path with suspecting some other turbo controls affecting the 2ndary turbo boost, rather than an issue with the CCA or its related solenoid. Something is reducing the boost generated by 2ndary turbo that Chamber A sees, because when you are supplying the right inputs to the solenoid the CCA is acting correctly.

Regarding the valve opening prematurely - you said before that plumbing chamber B into the intake causes the valve to stay stuck completely. I don't believe that the CCA can open prematurely so long as Chamber A sees vacuum and Chamber B sees some kind of pressure. Even if Chamber B had no pressure and Chamber A had some reduced pressure, the spring inside the CCA would make the CCA valve open at transition.

Do you have a boost gauge installed on your car? Is primary generating the 10psi/0.8bar?

 

Attached two highway logs of three pulls each. This is an auto car, so I'm low in 4th, it'll drop to 3rd and work back up. With B attached, I get instances where the CCA is clearly stuck open or fluttering as I bounce in the 5-7psi range. The one instance I get proper changeover it's a very slow rise from 7, down to 5, then up. to 11. I will say I know the primary isn't blown or having issues as from a dig, primary will easily jump to ~12-14psi. I can include any more traces or run other street tests as needed. There's probably a better test, perhaps a 2-3 run using the auto's HOLD, but I was trying to put as much load on the car to let the turbos work over raw RPMs.

Chamber B attached


Chamber B open.