Quantum Syncro AWD L5-2226cc 2.22L SOHC (1987)
Engine Control Module: Component Tests and General Diagnostics
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.
Full Throttle Enrichment
1.
Remove the plug from the coolant temp. sensor and connect the terminals together (use adapter VW 1490 or equivalent).
2.
Unplug oxygen sensor
3.
With ignition switched ON, activate full throttle switch.
4.
Current should increase approx. 3 mA when switch is activated.
5.
If the current does not increase, check;
a. Throttle switch.
b. Check for open circuit in wiring between terminals 5 and 2 of the control unit plug and full throttle switch.
6.
If the wiring and the switch are OK, replace the control unit.
Oxygen Sensor System
