I'm pretty certain one of my aux port actuators is not working/opening. I have a 1991 coupe NA, the actuators move up when they open. My haynes book tells me to use a 'T' connecting to the actuator hose, a pressure gauge and use low pressure CO2. For lack of tools, I blew into the hose and the actuator closest to the front of the car moved up a few millimeters, I have no idea how far is 100%. The one closest to the back of the car didn't move at all. NOW for an example of why I think they are not working, the same method of checking the vdi actuator is listed, I blew into the hose hard and I was able to open almost 100% if not 100%. The required pressure for both aux and vdi actuators to fully open on a 1991 is not listed but for an '89 the aux ports fully open at 1.4 psi and the vdi at 2.8. So I don't think the aux port actuators were not opening and hardly opening because a lack of effort on my part...???

 

What you can do is remove the actuators, and test them off of the Engine if they both work you can try moving the small arm back and forth to see if you can free them , I have done it but its not always possible, but more than likely you will have to remove the intake and clean the carbon and oil from the ports and actuators once you tear it down, as far as how they work the ports open up,and rotate up to the bent metal tab,(inside) and close ,on the far tab,once you have cleaned them, just remember to( once in a while) open the six ports by planting your foot on the floor,and going past 3500 rpm,they tend to stick if you don,t kick it in the *** every so often............................................. ....Fred

 

If they don't open it is because of dirt/carbon built up INSIDE the lower intake manifold preventing the rod that connects the actuator to the sleeves from moving.

I doubt the actuator itself is bad, but if you really think it's just the actuator, remove the two bolts that hold it in place, slide it off, and move it up and down. In fact you can blow air directly from your mouth to fully move the actuator.

 

if you do want to find out about part availability, call Ray Crowe at Malloy Mazda (forum vendor here). (866) 496-3613 ask for Mazda parts and then ask for Ray Crowe. He owns an FC and an FD.

 

+1.. same thing happened to my NA... i cleaned up the intake mani and the 6PI was functional again. i have some actuators i could sell u ..... $15 shipped.... but i dont think u need them

 

The auxiliary port actuators are just above the stock exhaust manifold, deep in the engine bay on the passenger side (1991 coupe NA). Why exactly do I want to clean the intake for the actuators to work, why not just the actuators and make sure the air pump works? Although cleaning the intake does sound like a good idea even if i was 100% sure the actuators worked because it probably hasn't been clean since 1991...

 

the actuators move a rod inside the intake manifold. this rod moves the sleeve which lets air into the engine... . first u need to make sure your actuators work %100... so remove em and move the arm by hand.... then install them and drive around and make sure they open... (u cant just rev the engine) if they dont move then and your air pump is working fine.. then u have carbon in the manifold....

 

take the actuators off and spray a little MMO inside the cam for the actuators arms in the LIM and a little on the actuator rods themselves on the solenoids, let it sit for about an hour then work them loose.

to clean them thoroughly requires removing the LIM from the engine and fully disassembling it.