Full Throttle Enrichment

Diaphragm Pressure Regulator Testing Connections:

1. Connect an ammeter between the differential pressure regulator harness connector and the differential pressure regulator, using VOLKSWAGEN special tool #VW 1315A/1 or equivalent.

CAUTION: The small female terminals in the differential pressure regulator harness connector are easily damaged. If fabricating a test harness, use the appropriate male terminals to make connections with the harness connector.

Coolant Temperature Sensor:

2. Remove the harness connector from the coolant temperature sensor and bridge the two terminals of the connector with a jumper wire.
3. Start the engine and raise to above 2500 RPM.

Full Throttle Enrichment Test:

4. Actuate the full throttle switch.
5. Measure the differential pressure regulator current.

^ Differential Pressure Regulator current should increase to approx. 16 mA.

If the correct measurement is not obtained check the CIS-E harness. Refer to SYSTEM ELECTRICAL TESTS. If the harness is OK the CIS-E control unit may be defective.