Insufficient Engine Power

Check fuel injectors.
Ensure fuel pressure is correct.
Check airflow sensor (if applicable).
Check for restricted exhaust.
Check coolant temperature sensor.
Check air temperature sensor.
Check engine speed sensor.
Check throttle switch and connector.
Check ignition and coil circuit.
Check MAP sensor (if applicable).
Check engine speed sensor or Hall Effect sensor (turbo).
Check intake and exhaust system.