KC_Michael

White arrow points to a broken small black hose that was attached to a nipple on the the bottom of the Y-pipe (right next to where it connects to the plenum/TB). Hose is around 3 inches long and attaches to the small grey plastic box. WHAT is this? What symptoms would this have caused? I just replaced the spark plugs and the car seems to be running fine. Would the leak in this hose have thrown any codes? Thanks in advance for any comments or suggestions.

jpflip

This is an important part of the turbo function. This grey box is the N75 valve (cycle valve) which control the waste gate function and the turbo boost. The part that is damage is only a very small elbow made in rubber and it is fix with a small clamp to a port on the intake assembly. Item#15 less than $10.00!

KC_Michael

Awesome! Thanks for your help.

powdrhound

In the picture of the N75 valve above, the broken hose on the left of the valve is the N75 bleed off air that get recirculated to the Y pipe. Of the remaining two hoses that connect to the N75 valve, the one to the right and one to the botton of the valve, which hose comes from the compressor side of the turbo and which hose goes to the wastegate? Its impossible to tell from the schematic.....

jpflip

If you follow the hose and and see the T fitting # 38 , that is where the hose split #37 and goes to both waste gates.

powdrhound

Ok, so he hose pointing down from the N75 sends pressure to the wastegates. Now if you look at the schematic, what is it that hose #41 and #42 are connected to form the N75 valve? They should be connected to the compressor side of the turbo but the schematic shows something different...?

jpflip

#41 and #42 (plastic rigid line going over the alternator (or generator) goes to the "F" hose where the pressure is tap for the waste gate operation. The F hose got also , attach to it, the diverter valves or blow-off valve which is also the pressure side of the turbo.

powdrhound

So to sum up, the compressor pressure is tapped from the "F" diverter valve hose and goes via line #42 and #41 to the N75valve where some of the pressure is bled off (and is routed to the intake manifold through line #15) while the rest of the pressure goes via line #40, #38, and #37 to both the wastegates.

jpflip

Exactly. Has you can see you got an item#37 on the left and on the right of the drawing because the right hand waste gate is not shown....