Fuel injection system (KE III-Jetronic) — additional adjustments and checks (Audi 80 B3)

Table of contents: Memory damage ↓ Lambda control ↓ Cold Acceleration Enrichment ↓ Cold start valve ↓ Throttle switches ↓ Diaphragm pressure sensor ↓

Memory damage

1. The KE III-Jetronic system is equipped with a fault memory common to the fuel injection system and the ignition system. The self-test procedure is described in Section 4, Chapter 8.

Lambda control

2. Connect the multimeter to the differential pressure regulator.

3. Allow the engine to warm up to normal operating temperature and run in idle mode for two minutes.

4. Note the current in the control circuit, then remove the level measuring probe, the current in the control circuit should increase. If not, disconnect the Lambda sensor wires and ground the green wire for about twenty seconds. If the current in the control circuit now changes, the Lambda sensor is faulty.

Cold Acceleration Enrichment

5. Disconnect the temperature sensor wiring and connect a digital potentiometer with a 3 kOhm resistance. For this, you can use a VAG 1630 digital potentiometer.

6. Start the engine and set it to idle mode, measure the current in the control circuit.

7. Quickly open the throttle valves, the current in the control circuit will briefly increase by 6 mA.

Cold start valve

8. See point 5.

9. Remove the cold start valve and place it over the measuring cylinder (photo).

10. Turn on the starter and check that the "cone" of the injected aerosol is even.

11. Wipe the valve dry.

Throttle switches

12. Throttle switch 1 indicates the closed position of the throttle, and switch 2 indicates the fully open position of the throttle.

13. The inspection requires the use of special tools, therefore, entrust this work to an Audi dealer.