Date:         Tue, 25 Sep 2007 10:18:44 -0700
Reply-To:     Michael Elliott <camping.elliott@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Michael Elliott <camping.elliott@GMAIL.COM>
Subject:      The two throttle valve switches
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

(1.9L)

Lemme see if I have this right. There are two switches on the throttle
valve. One closes when the foot is off the gas pedal, one closes when the
pedal is floored. They are wired in parallel and both connected through
one single wire to Pin 4 of the ECU. So how does the ECU know which switch
is closed? Here's the best I can figure out so far:

IF ECU(4) is pulled low because foot is off pedal (closing idle switch)
AND engine rpm is less than 1500 rpm, ECU shuts off fuel to the injectors.

IF ECU(4) is pulled low because pedal is floored (closing full throttle
switch) AND engine RPM is ABOVE ??? rpm, ECU assumes acceleration is
wanted and it increases amount of fuel injected.

Since the two switches are connected to the same ECU pin, there must be
some logic involving engine rpm, but it's not clear to me how this works.

Someone point me to an article on this?

--
Mike "Rocket J Squirrel" Elliott
71 Type 2: the Wonderbus
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
KG6RCR