Connect scan tool with 'DATA LINK CONNECTOR' (DLC).
Warm engine up to normal operating temperature.
Turn all the electrical devices including air conditioner OFF.
Monitor "FUEL QUANTITY" parameter on the scan tool.
Fig.1) Injection Quantity at idle
Fig.2) Injection Quantity at 4,000 rpm
☞ "FUEL QUANTITY" is a sample data from randomly selected a injector among cylinders. Therefore, thoroughly check all the symptom through the "compression pressure and fuel line" with scan tool.