3.
Monitor the "HO2S OUT VOLT(B1S1)" parameter on scantool.
1)
Specification : Verify that the signal is switching from rich(above 0.45V) to lean(below 0.45V) a minimum of 3 times in 10 seconds (voltage will vary between 0.1 and 0.9V).
Visually/physically inspect following items
- Inspect HO2S for silicon contamination from fuel or use of improper sealant. The HO2S may have a white powdery coating and this will result in a high but false voltage signal (rich exhaust indication)
Warm up the engine to normal operating temperature.
Monitor the "HO2S OUT VOLT(B1S1)" parameter on scantool.
Specification : Verify that the signal is switching from rich(above 0.45V) to lean(below 0.45V) a minimum of 3 times in 10 seconds (voltage will vary between 0.1 and 0.9V).
Is the sensor switching properly?
YES
HO2S is ok
Possibility of ECM fail
Test with a new ECM sensor and check for proper operation. If problem is corrected, replace ECM. And go to "Verification of Vehicle Repair" procedure.
NO
Test with a new HO2S and check for proper operation. If problem is corrected, replace HO2S.
Go to "Verification of Vehicle Repair" procedure.
