Emission Control Systems: Testing and Inspection

Fig. 11 Lambda sensor wire:

1. Disconnect wire 141 from the Lambda sensor, Fig. 11.
2. Start engine.
3. OCR tester should read 60% (54° on dwell meter).
4. If value is incorrect note the value read and stop the engine.

Fig. 24 ECU connector pin # 2:

5. If the OCR reading moves toward the maximum connect an ohmmeter between terminal 2 of ECU connector (wire 141) and ground, Fig. 24. Resistance should read "infinity"
a. If value is incorrect, check the insulation of wire 141.
b. Put the ECU connector back on.
6. If OCR value is not at 60% (54° on dwell meter) and does not move toward the maximum.
a. Run the test again with a new ECU.

Fig. 12 Lambda seneor wire - grounded:

7. Ground Lambda sensor wire 141, Fig. 12.
8. Start the engine.
9. The indicated value on OCR tester must move toward the maximum.
10. If the indicated value does not move toward the maximum but is equal to 60% (54° on dwell meter) check the continuity of wire 141 between Lambda sensor and terminal 2 of ECU connector, Fig. 24.
11. Once this is done, reconnect wire 141 to Lambda sensor.