Engine running fine, but out of the blue the actuators aren't working at 4000 rpm as the should. They aren't seazed cause I can move the rod up and down and they are always checked. Anyhow I figure that It has to do with the exhaust pressure not getting to them. Now I wasn't sure how it goes Is it vacuum that opens them up or is it the pressure from the exhaust?

 

it's a 2PSI pressure from the exhaust

 

Thanks man!! BTW the car is look'in good!! You used to have the 2nd gen wheels right?? The stars make a huge difference!!

 

How did you check them? Did you use a vacuum guage?
Just wondering as I was about to check mine.
And mine can be moved by hand, but I don't have a vacuum guage to "T" up to the actuator line to test it.

 

For a quick teat, I think you could simply attach a length of hose to them and blow in to it a little to see if they'll move. A few pounds isn't much.

Isn't it back presure, NOT vacuum that actuates the port secondaries? Like abeomind said? Then it's not a vacuum gage.