5000CD Quattro Sedan (Canada) L5-2226cc 2.22L SOHC Turbo (MC) (1988)
a. Air flow sensor potentiometer
b. Wiring circuit to control unit (terminals 14, 17, and 18 on control unit, and 3, 2, and 1 on potentiometer).
8.
If circuits are OK, replace control unit.