ISV
Idle Stabilization Valve
10 V Mc - II above, 3B 20V below
Audi used these units to stabilize idle during lift throttle.
Here is a 10V (told to me by Chris) unit I bought.
I needed one for a MC -II Part number 035 133 455 F
Here is the whole unit.
This is the connector end were people tell us to check
the solenoids operation by attaching a 9V battery.
Radio shack has the plastic 9V top connector
and two wires coming out part for ~ $2.50
Inside the top (side port) of the unit we can see the valve inside.
Here is the direct view from the Intake Manifold (IM) boot.
CLEANING:
Most people just take out the ISV, spray Carb.,
or throttle body cleaner inside and reuse.
test solenoid with a 9 Volt
Check for air leak when (valve) closed on the port.
3B 200 20V (1991) ISV
Below is the ISV which is different that the 10V version shown above.
Location shown here on top of the Intake Manifold. (IM)
ETKA (older version) shows this on Illustration 16 - 50 as:
PN # 034 133 455 B
HTH - Scott
E-mail to SuffolkD@aol.com