1990 Audi 100 Base, AutomaticFACTORY OEM SERVICE PROCEDURE

Full Throttle Enrichment

  1. Using Adapter Cable (US 1112), connect Green test lead to OXS system test connector (Blue/Black wire). Connect Dwell Meter (VW 1367) to vehicle. Set the "%" button on dwell meter.
  2. Disconnect vacuum hose going to ECU. Remove throttle switch. Start and allow engine to idle. Bridge throttle switch terminals No. 2 and 3. Ensure dwell meter indicates a constant 60% duty cycle. If not, check continuity of throttle switch wiring back to ECU.
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.