I have seen a 3 port bleed valve and 2 port I know the a 2 port fits betwwen the actuator and turbo to adjust boost what is the 3 port one for ?
Can it be used in the same way ?
Thanks.

 

I think that the third port goes back into the intake after the airflow sensor.
I stand to be corrected though!

 

I thought it may have been to hook up a boost gauge I don't understand why they have a 3 port at all anyone clarify the difference and if it can be used in the same way as 2 port ?.
Thanks.

 

anyone answer this ?

 

3-port gives massively superior control:

A 2-port solenoid gives an ECU controlled bleed from the pressure line to the actuator: there is a restrictor inline to stop the solenoid bleeding all the pressure at once.

A 3-port solenoid (as mentioned) has a restricted line back to the inlet.
But the +ve pressure line from the engine goes direct to the actuator (no restrictor).
This means the solenoid is switching between a vacuum and +ve pressure.....so the solenoid does not have to 'wait' for pressure to bleed from the actuator. This means superior actuator control, as the solenoid cycle is not 'damped' by the restrictor.