Wait. I got this wrong. Lemme try again.

On the earlier 1.9L's there are two switches on the throttle valve. One
closes when the foot is off the gas pedal, and the other closes when the
pedal is floored. They are wired in parallel and both connected through
one single wire to Pin 4 of the ECU per Bentley's 97.55. Both switches
ground Pin 4, the ECU doesn't have any way to know which switch did it.

Now if the engine is at 1500 rpm or faster and you take your foot off the
gas, the idle switch closes, grounding ECU Pin 4. Bentley's says that
under these conditions, the ECU shuts off fuel to the injectors (24.33).

But if you /floor/ the pedal, the full throttle enrichment switch closes,
which ALSO grounds ECU Pin 4. Bentley's tells us that when this happens
the ECU will enrich the mixture (24.34).

So taking your foot off the gas or flooring the pedal both ground Pin 4
... so, uh, how does the ECU know whether to shut off the fuel or to
enrich the mixture?

--
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