The easy way is with a meter. The idle switch completes the ground path
(current sinking) for the ecu. You will see ~ 5 volts across the contacts.
The auxiliary air regulator gets 12 volts.

The switch is adjustable from above. You need a long 3mm allen wrench. The
larger screw head is the clamp, the smaller one turns a cam.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Mike Collum
Sent: Saturday, August 26, 2006 6:27 PM
To: vanagon@GERRY.VANAGON.COM
Subject: TPS wiring

When I redid the heads on my '85, back in '02, I labeled all wires and
put them back where they were when I got it.  Some of you may recall
that I only went 280 miles before the headgaskets blew, so the van was
new to me at that time.

Anyway, it has the single (newer type) TPS and my question is what is
the sure way to tell if the wires to the aux air reg and the TPS were
reversed by a PO?

Lately, it's been idling much too fast after highway driving so I
manually operated the throttle (engine off) and I can hear the TPS click
for WOT but no click coming off idle or going back to the idle position.
That means I'll have to take the throttle body off to clean and check
things and I wanted to be sure, especially if I have to change the
switch, that the right wires are connected.

Thanks,

Mike