Inspection Procedures
- CHECK OTHER DTC
- Connect Hi-Scan (Pro) to data link connector.
- Turn ignition switch to ON and monitor other DTCs.
Are any other DTCs also set?
No: Go to next
Yes: Do all repairs associated with those codes before proceeding with this procedure.
- CHECK HO2S AND ECM CONNECTORS
- Thoroughly check connectors for loose, poor connection, bent, corrosion, contamination, deterioration, or damage.
Are all connectors good?
Yes: Go to next
No: Repair or replace it.
- Thoroughly check connectors for loose, poor connection, bent, corrosion, contamination, deterioration, or damage.
- CHECK INTAKE AND EXHAUST SYSTEMS FOR LEAKAGE
- Visually check intake and exhaust systems for leakage.
Is any leakage present?
Yes: Go to next
No: Repair it.
- CHECK FUEL LINE PRESSURE
- Start engine with the fuel pump disconnected and wait until stopping by itself to release fuel pressure.
- Attach fuel pressure gauge to fuel delivery pipe.
- Start engine and check fuel pressure at idle.
- Refer to FUEL PRESSURE TEST .
Is fuel line pressure within specification?
Yes: Go to next
No: Check fuel delivery system. See FUEL DELIVERY SYSTEM .
- CHECK HO2S SIGNAL WAVEFORM
- Reconnect HO2S and ECM connectors.
- Warm up engine to normal operating temperature.
- Using Hi-Scan (Pro), monitor HO2S signal waveform.
Do the front HO2S signals fluctuate between 0V and 1V?
Yes: Proceed with ECM PROBLEM PROCEDURE .
No: Replace HO2S.