By Pass Valve:

Click here to do this mod to a 10V 200

Blow off valve, dump valve, "cut off" same thing.

Audi: 06A 145 710N  Newer TT part.

Audi: Old "cut off valve" 034 145 710A

Part Number: 0-208-142-106 (older) or 9 (below)

Here is the replacement of the OEM (upgraded) Bosch 710N.

Examples found here at

NOTE VALVE ORIENTATION.   Valve must go ONE way.

The little clamp is a squeeze type.  Difficult.

The crimper tool is identical to a irrigation installation clamp tool.

The top of the valve is fed by vacuum through the braided hose.

Its the black sideways canister, dead center of the photos above & below.

There are two clamps, slotted for screw drivers. 

We used a 1/4" socket wrench.

Top clamp above, bottom clamp below.


Valve must go ONE way.

To test old valve diaphram, apply or make vacuum to the "inlet" end.

If air leaks by (vacuum is lost) valve is bad.  Possible to clean.

  Valve must seal to work correctly.  Part does not disassemble

Swap out old one and put in new one. 

Piston aftermarket one supposedly don't tear and are cleanable.