Im new to the list. I just recently aquired my first vanagon, 1984, 1.9
water cooled.  Replaced exhaust, found gaskets, got it quiet, then new
plugs, new rotor and cap and wires, and it runs halfway decent.  O2 sensor
made a huge difference.  Now, I note that the throttle valve switch is
missing. I believe that this is the model that only had one switch as I can
only find one lead hanging.  Can anyone tell me how much difference the
switch makes in performance?  The van runs good, although backfires
occasionally after I have my foot in it working my way up the hills around
here.