Uh, boy, that sux. Bad. Based on how you are trouble-shooting, ‘tho, I don’t know of you’ve proven your wiring is working on pin 3. Maybe test that it’s indeed getting shorted to ground before you commit to your new actuator? Doesn’t it’s behavior off the car allude to: “yes, pins 1+ 2 are working, but pin 3 might not be?”OK, so bad news for me, good news for all of you. I have confirmed that my active runners are not actuating. As a result, the dyno result I posted is significantly more straightforward showing only the benefit of adding the short tube headers.
I know I've seen other R/T dyno's with the 392 intake which showed a big dip in power when they haven't been tuned to account for the extra airflow after they go short mode. I found it odd that I saw no power dip in the baseline run, so I had to investigate. I double checked the wiring and confirmed that I have 12 V, ground, and the actuator wire throwing ground when engine speed surpasses the ON-RPM, so I am confident that the wiring is OK. I ended up sticking a borescope into my intake manifold and just watched the flaps as I changed the ON-RPM setting over and under my idle RPM to test functionality; they're not moving.
I've removed the actuator and I can move the flaps by twisting the knob that the actuator couples to by hand. The flaps move freely, so they're not stuck or anything.
I then plugged the wiring back into the actuator and left it out to watch its behavior. I had to tape the hole on the backside of the intake manifold to turn the engine on, and upon doing so I note that the actuator performs a single actuation cycle when the car turns on, then nothing. The fact that it can always cycle once on startup tells me that my circuit delivers the required current to make it operate, but for whatever reason it is blind to the "actuate now" signal.
I feel reasonably confident that the problem is the actuator, so I'm going to replace it and see if it behaves. It should be ready for pickup on Monday. In the mean time, I'm gonna sit around being pissed at myself for not figuring this out before I paid for the tuning session.
This may be a great case to try the 5v LED trick on pin 4. That should tell you if the wiring to pin 3 is functional.