Inspection Procedures

1. Connect Hi-Scan (Pro) to data link connector.
2. Turn ignition switch to ON and monitor other DTCs.

Are any other DTCs also set? 

No: Go to next step.

Yes: Do all repairs associated with those codes before proceeding with this procedure.

1. Thoroughly check connectors for loose, poor connection, bent, corrosion, contamination, deterioration or damage.

Are all connectors good? 

Yes: Go to next step.

No: Repair or replace it.

1. Start engine with the fuel pump disconnected and wait until stopping by itself to release fuel pressure.
2. Attach fuel pressure gauge to fuel delivery pipe.
3. Start engine and check fuel pressure at idle.

• Refer to  FUEL PRESSURE TEST  . 

Is fuel line pressure within specification? 

Yes: Go to next step.

No: Check fuel delivery system. See FUEL DELIVERY SYSTEM .

1. Reconnect HO2S and ECM connectors.
2. Warm up engine to normal operating temperature.
3. Using Hi-Scan (Pro), monitor HO2S signal waveform.

• Refer to  SIGNAL WAVEFORM   for more information. 

Is the rear HO2S signal normal? 

Yes: Proceed with ECM PROBLEM PROCEDURE .

No: Replace HO2S.