Engine Hesitates Or Misses

Ensure electrical harness, connectors and wires are not broken or loose. Check ECU connector pins No. 9, 11, 13, 17 and 25, and all input signals to ECU.
Check charging system for low output and poor ground connections. Check all electrical connections for tightness.
Check injector operation and opening duration. Check injectors for leaks.
Check turbo and Automatic Performance Control (APC) systems for proper operation.
Check throttle position sensor.
Ensure mass airflow meter filament is not broken and burn-off function is working.
Check induction system. Check for air leaks downstream of throttle valve. Inspect duct between mass airflow meter and throttle body.
Ensure fuel pump is okay. Check fuel pressure and pressure regulator. Check for fuel leaks or restrictions in return line.
Check temperature sensor.