Searching and searching but just getting more messed up here. My son's 86 fc (his first car) seems limp above 3000 and we have adjusted everything we can think of.
Compression is even and not missing in either port (above 80),
new wires, plugs, adjusted idle and tried for mixture adjustment by ear (previous owner had it fully to the lean side which we thought might be contributing the the slightly hotter than desired running temp).

Doing the grease test on the actuators and looks like they are not moving.
Searching the forums I am getting a bit lost as to whether these are push-in (pressure applied) or pull out (vacuum applied) actuators and if they are exhaust or vacuum line driven. I want to try to test on the car (if vacuum driven with a small hand vacuum pump) before I try to pull stuff off.

Any clear instructions would be appreciated.

Thanks.

 

Post #17 and #18

https://www.rx7club.com/2nd-generati...ators-1033148/

 

They're push in style. Here's a good write up on how to test them:
How To Test Your 5th and 6th Ports

If it's noticeably limp I'd say something else is wrong. I've had my actuators both working and not working. You can feel a slight bit of "boost" when they open but with them not working the car still has plenty of power.

 

My son and I have read that link many times. Easy enough to follow BUT
I have 2 sets, one on the car and an extra off and they are push out style.
Both sets are driven by exhaust.
I checked them by: crawling underneath and unclipping the rubber line from the exhaust. I felt exhaust pressure coming out of the exhaust side of the tube so that's not blocked.
I then joined a longer line to the rubber one leading to the two tubes-actuators and blew in and they both moved.
Reconnected everything and we checked visually by revving up to around 3500 and they did both open but only about 1/3 of the way.

Either the exhaust isn't pushing enough through to the actuators (aftermarket exhaust) or both actuators are a bit tired.

We were thinking of removing the two and swapping for the other two, both seem to have good action and holding our fingers against the inlet ports showed no loss of pressure when moving the shaft (or they would have moved freely) but we do not have gaskets with us.
Stopped for now to deal with pesky p/s leak.

 

have you cleaned all the grounds?

did you make the adjustments to the variable adjuster according to the FSM (not by ear) WITH the check connector jumped?

also, if you only got 80 PSI for compression the engine is starting to get tired, and you may be fighting a losing battle

 

90 psi (and forgot to open the throttle fully so will test again).

The FSM shows a manual test by applying small amounts of air pressure and checking. 1.2 psi for starting to open and 2.1 psi for fully open.

the ODD thing is the FSM shows the arrows indicating that the plungers move inwards with air pressure BUT mine are connected so that they move outward when air is applied. I did this by attaching a tube and blowing into it. Also, re attaching it all an revving to 3500 did cause the actuator arms to push OUT and the pivot mechanism only moves in one direction as there are built in stops. Wondering of the previous owner or someone connected them wrong?

Looking at the drawings, it really isn't clear if the arrows are indicating that the direction for the arm should be in or out or if they are indicating the back-forth rotation of the pivot (cam?)
Will try again and maybe attach a short video clip.

scan of page 60 attached

 

Correction, they do push out and the cam rotates downward.
I applied some air to the common inlet and find that at 1.2 psi they start to move (but the firewall side one less so) and at 2.0 the one towards the rad closes fully and the one near the firewall only about 60%.
Removed the suspicious one to check and find the top port of the manifold seems blocked off.

Has anyone come across this before? Seems harder than carbon buildup and is dark grey.

 

Exacly where are you looking? Do you have the manifold off?

 

Thanks Tony.

Manifold is on. Looking at mounting studs for actuator (rear one). There are 2 small exhaust ports. One next to each stud. The top one seems blocked. I don't want to pull off the front as that will require making another gasket so I will make one for the rear and fit my spare actuator. If better, then it is the actuator. If not, i have to think the front is not sealed off and the rear was for some reason or it is build up.

 

the variable adjuster is NOT mechanical, and the FSM in the emissions section almost ALWAYS starts out telling to jump the test connector, I've read it many times and have done it many times. Look up the idle relearn, IIRC it is in the emissions section of the FSM

 

its under 4a-77 thru 79, VERY first step is to jump the test connector

 

Maybe satch will chime in again ..BUT I sort of recall the Map sensor having to be blocked off or what ever in order to test the engine at over 3500?..
That would then be at enough rpm to build back pressure and activate your port actuators?

*I could be wrong,so I'll leave it at that..

When I had my S4 N/A I would reach down and move the arm on the actuator to see if it was gummed up at the shaft.I'd spray with some silicone lube and work it to get it sliding freely.I have taken them off and wire them open,replaced the whole workings of the lower manifold and sleeves etc..The thing you have to watch is that plastic shaft to the sleeve and make sure that it you do not bust it IF you try to get the sleeves to move with the actuators off.
Also you should look "way back" and get the direction of the motion of the actuators themselves as S4 goes one way and s5 goes in another direction.
(I think I asked that years ago,so if you need to you can use my name as a "user name" when you search "port activation" as a subject under advanced search)

 

O.K. I think we are getting answers to two issues here. Testing engine electrical and testing actuators.
Let's ignore the engine for now and deal with the actuators.
These are mechanical (exhaust driven) only. The direction of movement is correct and I have an extra set.
Holding my fingers over the inlet ports on the actuators and then trying to push down the plunger shows resistance and no leaks so I expect they are fine.
I removed one completely and when swapping another over, noticed that the top port on the manifold seems blocked off and it does seem like a metal plug. There are two ports, one near each stud.
I connected the newer actuator with a new gasket and blowing in 2 psi found that the rear one still lagged and would not close completely.
Removed that actuator, unhooked the swivel cam and reattached the actuator to the manifold.
Blew in 2 psi again and both closed completely.

So: Either the actuator is fine and the rotating part inside the manifold is stiff (I can't tell, never moved one by hand)
or the actuator is fine but the p.o. plugged done hole for some reason and that is affecting the amount of pressure reaching the actuator (unlikely)

I guess I have to remove the front actuator and compare the movement of the cams.

A bit concerned about removing the inside pieces as those mounting screws seem a bit flimsy and busting one off will only make things harder.

More searching ahead and thanks

 

That is for the S5, got to unplug the map sensor.

Easiest way is to put grease on the lever, go for a drive, and see if it moves after you parked.

 

Had come across some images of the sleeve and removal procedure but not able to find it now after much searching. Any pointers would be appreciated. Hoping to remove actuator from front and compare shaft rotation and if back shaft is stiffer, remove and clean but don't want to start unless I have some decent reference images to make sure I don;t create a bigger problem.
Hoping to post an image of the manifold port holes showing the plugged off top one for reference.

 

Your best bet would be to remove the entire intake system and take out the sleeves and clean them, and everything else in the intake, then reassemble with all new gaskets. Not a hard job really except remembering where all those pesky little vacuum lines go, but that is easily remedied with some ingenuity

 

Got an easier solution that can work. Worked for me anyway....

On my S5, I poured some seafoam down the big vacuum line on the back side of the intake (between the secondary intake runners). It will just sit there until the secondaries open and the 6pi system opens. Until you really get on it and go above 3500, it will just sit there patiently, but when you really get on it, the engine will suck it in and you'll be James Bond.

 

Not sure where that big vacuum line is but will look through FSA again. Would be much easier than pulling out sleeve I think.

 

Only thing that would worry me is the possibility of a bis chunk of carbon getting sucked in them destroying the engine

Course even if you take the whole intake apart and pull the sleeves out, thats still a possibility