Ok, I have an 88 na. The sleeves turn fine. The rods turn fine. The actuators themselves seem to retract into themselves relatively freely. However, I cannot get the actuators to retract when reving up. I tried removing an actuator and feeling in the vacuum 'hole' for air, which there is (though I'm not sure how much is supposed to come out), and it increases as revs go up. My problem now is that it seems all service manuals I can find are for 89's (88's have no hose to check vacuum). Can anyone help me out on this? Also, which selenoid is the one that controls the actuators on an 88 na, or is this even how the system works for my car?

 

Why don't you remove the port actuator tube which comes up from the exhaust and is about a 1/4 OD tube. Then connect the tube to the other side of a vacuum pump to get pressure and see at what pressure they open at. BTW got a free flowing exhaust system?

 

No, but I do have a high flow cat and cat back. So is it just back pressure from exhaust that activates the actuators? Does the ACV have anything to do with it?

 

You're not giving it enough throttle when revving the engine. The actuators work with exhaust pressure. To get enough pressure in the exhaust you need enough exhaust flow, and to get enough flow you get to open the throttle further. Be careful not to over-rev...

 

The port actuators are supposed to start to move at 1.3 psi and should be fully open at 2.1 psi according to my '88 FSM. Go to a parts store or tool supplier and buy a vacuum/ fuel pump gauge (inexpensive) and about 4 ft. of vacuum hose, same size hose as the actuators use (5/32'' i.d. i think), and a vacuum tee fitting. You want to "t" into the pressure supply hoses at each actuator and tuck your pressure gauge under the driver's wiper blade so you can watch the pressure while you accelerate. If you don't see 1.3-2.1 psi, then attach your gauge's hose right to the actuator's pressure hose without the tee (direct connection). If you now see correct pressure when you accelerate, the actuator diaphragm is ruptured. Repeat for the other actuator. If there isn't correct pressure when the gauge is directly connected to the exhaust supply, there isn't enough backpressure, possibly from exhaust mods.