Check At O2 Sensor: Diagnosis
- Start engine and bring to operating temperature. Increase engine speed to 2500 RPM and note gauge. Reading should not exceed 1.25 psi (.09 kg/cm2 ).
- If specification is exceeded, exhaust system restriction is indicated. Check complete exhaust system for collapsed pipe, heat distress and possible internal muffler failure.
- If none of the conditions in step 2) exist, check for restricted catalytic converter. Replace if necessary.