Hi Rob:

This procedure I found on a Porsche related web site, which uses the same
type of aux air regulator as ours. My aux air regulator had been bypassed by
the previous owner with an after market unit (to support AC) and had been
left in the engine compartment for 20 years. It had gathered all sort  of
junk and did not work.

I needed to clean it out and test it to see if it could be used. I am
assuming that you tested the electrical resistance of the unit per Bentley's
first.

1. I loosened the adjusting screw and manually tried to move the valve (mark
where the screw was first).

2. I soaked it in paint thinner, then used some acetone to clean out any
remaining gunk.

3. put a light weight oil into the unit and used a small screwdriver to very
delicately make sure that I could open the valve and that the spring could
close it most of the way.

4. Now we know that we have a valve that should work and we can test. Place
the valve in the freezer for about 15-20 minutes. While waiting heat the
oven to 200 degrees.

5. After 20 minutes in the freezer the valve should be fully open. Adjust if
necessary.

6. Place in the oven. After 11-20 minutes check on the valve. It should now
be closed fully. On the engine this happens faster as the aux air valve has
an internal heater plus the heat of the engine.

7. Using a hose and a pot holder, suck air in through the valve in the
direction of the arrow (on top of the unit). The valve should let no air or
a small amount of air through. Mine stopped air in less than a second as the
metal sealed against itself.

My valve now works fine. I will see if I can find the Porsche site and post
it to the group.

Good luck

--Jeff Strickrott
82 Westy, South Florida

Rob Wright wrote:

> Does anyone know a good way to test the air regulator on an 84 1.9
> motor. i am looking for something behond the Bently procedure. I pulled
> the hose off when the van was cold and it was only slightly open. Should
> it be all the way open? Or does it depend on outside temps? Does it need
> to see voltage to open or close?
>
> TIA Rob Wright