Component Inspection

■ Check HO2S 

1. Visually/physically inspect the following:
   • Ensure that the HO2S is securely installed.
   • Silicon contamination. This contamination will be indicated by a white powdery coating on the portion of the sensor exposed to the exhaust stream and this will result in a but false (high) voltage signal
   • Fuel, engine coolant or oil contamination
   • Use of improper sealant
   • If contamination is evident on the HO2S, Fix the source of the sensor contamination before replacing the sensor to prevent future contamination. Go to "VERIFICATION OF VEHICLE REPAIR " procedure.
2. Was a problem found in any of the above areas?

   YES 

   • Repair the connector. Go to "VERIFICATION OF VEHICLE REPAIR " procedure.

   NO 

   • Substitute with a known-good component and check for proper operation. If the problem is corrected, replace component and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.