My Passat 1993 with 280000 Km lost it's idling control. The motor was running 400 - 500 RPM instead of it's regular 900 and the Air Idle Controller motor in front of the single injector was buzzing ftantically. I opened the sealed unit and discovered that the DC motor shaft that's inserted in the worm gear has eaten the flat surface and is rotating loose in the plastic. It was glued in place using epoxi and now the idle pusher is functioning. The whole injector house was cleaned with solvent, now it idles with control of the regulator but after warmup istarted rising to 1500 and fallin, rising to 1500 and falling, If I disconnect the left connector on the throttle position and reconnects it stops rising to 1500 RPM, till it touch the throttle cable.. returns to the unsteady state. In driving it has a dead band between 1200 - 2000 RPM . In high speed it runs nicely. What did I do wrong? some passage got clogged while cleaning? In the end of the idle pusher there is a spring loaded switch that senses that the trottle butterfly is not touching the idle pusher. It opens electrically an air valve in the body, I can hear that the tone is changing I'm playing with that switch.
Any suggestions? Thanks Eyal