Turbo Functional Diagram
 

Turbo Diagram


See attached image

Neat picture, needs a little text.

What do you suppose item Y30 does? Not just a name but the true purpose.

I agree with U, poor schema
 

Y30 : Is a switch-over valve that protect the engine from overload.

When disabled : the intake manifold is directly connected to The ALDA "103" on the top of the IP. It enters in action if the waste-gate "=Boot pressure control valve"on the Turbo body doesn't open when the pressure reaches ~0.9, this event send an electrical signal (thanks to the pressure switch "S66") and cuts the flow to the ALDA that consequently stop providing diesel.

I didn't put names on the diagram, I supposed that everybody know how it works. ;-)


Please correct if Imy explanation isn't OK.

Sounds good to me.

Switch S66 does in fact ground at a specified level of boost causing the switchover valve Y30 to close off the pressure (boost) signal from the intake to the aneroid (ALDA). The aneroid is attached to the governing mechanism and reacts to pressure. It handles altitude changes and boost fuel correction. Without the boost fuel correction the additional air has no fuel to make power and the car drives like it doesn't have a turbo.

thanks a lot Steve,

Just one question, Yesterday, I turned the screw on the ALDA, 180° anticlockwise, I thought that this increases the fuel delivery for the same pressure, ans so more power, unfortunatly, I've noticed no added power, just an increment of RPM at Idle.

:confused:

Should I put it back to its initial position ??