ADJUSTING IDLE SPEED AND CO - USA AND JAPAN {Beginning with 1983 Models - L-Jetronic)

Note: Requirements:

Engine in perfect mechanical condition and ignition timing adjusted correctly.

1, Fold up foot support in footwell on passenger's side and disconnect oxygen sensor plug.

2. Take off cover of exhaust source line in engine compartment.

3. Connect exhaust probe US 4492 on exhaust source line.


If there is suspicion of erratic engine running or when troubleshooting, it is advantageous to use test connection on the catalytic converter.


Use separate tachometer from tester or similar,

Make adjustments as quickly as possible to avoid excessive heat in intake ports and consequently wrong CO values.

7. Check CO. If CO is not as specified, correct the air flow sensor adjustment.

8. Reconnect oxygen sensor plug after finishing adjustments.

4. Run engine to operating temperature (oil temperature approx. 80 °C). Use Special Tool US 8025.

9. Coat threads of plug for test connection on catalytic converter with Bosch Paste VS 140 16 Ft or Optimoly HT.

Tightening torque = 15 Nm.

5. Connect CO tester to supplier's instructions.

6. Turn control screw or bypass screw on throttle housing until specified speed is reached.

24 - 6 d Adjusting Idle Speed and CO - USA and Japan, 1983 Models

CHECKING FUEL PRESSURE - USA and Japan (from 1980 Models with L-Jetronic)

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