One hand warmed with coffee, and another hand cold with wrench, I did an experiment.  With just the meter attached to the window,  the airbox and several acres of plastic cover removed, I drove until the voltage disappeared again.  It hiccupped on a curb near a grassy knoll,  and I formed a conspiracy theory about Volkswagen engineers targeting me.  In the fog, sliding on the dewy morning grass next to the road, the car still running, I started yanking on wire harness.  This car has lots of wire.  One eye on where I was sticking my appendages, the other on the 4 zeros across the screen.  I worked my way from the TCM under the windshield, across the plenum, down the plastic channel, all the way to the plug.  Nothing but 4 zeros.  Humph.  On the other end of one of those wires, the output speed sensor is buried where I cannot see it, even with all the plastic off. To small a gap to even fit a finger.  I wiggled what I could get at, then a tiny voltage jumped.  Not the voltage across that wire, the voltage across the other sensor, the input speed sensor.
A light bulb exploded over my head. Was this kraut box was using the same supply across both sensors?

Posted on June 4th, 2009 by admin
Filed under: Uncategorized