Cold Acceleration Enrichment
Fig. 7 Differential Pressure Regulator Test Setup:
1. Connect differential pressure regulator test harness (VW 1315A/1), Fig. 7, and hook up a multi-meter set for 0-200 mA.
2. Unplug harness connector from coolant temperature sensor and leave open.
3. Open throttle so that idle switch is open (no continuity).
4. Remove boot from air flow meter.
5. With ignition ON, quickly lift sensor plate fully and observe meter reading.
6. Current should briefly increase to at least 110 mA, then drop to 80 - 110 mA.
7. If current does not fall within specifications, check;
a. Potentiometer
b. Wiring circuit to control unit.
c. If wiring and potentiometer are OK, replace control unit.