i have also looked at a wiring diagram on tolerence and could not see anything to do with the exhaust flap, How-ever i am led to believe it must be pcm controlled due to the fact it opens and closes depending on throttle position and rev-range it could however have its own control box that i am un-aware of .

i have substituted the valve for a good known working egr vacuum valve similar in design but a bit bigger, it still plugged in and there was no change. I have nothing to supply it with a pwm signal so have not tried to power it up off the car

so does anyone no what controlls the exhaust flap on 330's?

thanks again

matt