Lack Of Power

On M/T models, ensure clutch is not slipping.
On A/T models, ensure transmission is not slipping.
Ensure brakes do not drag.
Ensure tire size and air pressure are to specification.
Check throttle linkage operation.
Check ignition timing.
Ensure ECM terminal voltages are okay. See PIN VOLTAGE CHARTS article in the ENGINE PERFORMANCE section.
Check intake manifold vacuum. Vacuum should be more than 17.7 Hg at idle.
Check air filter element.
Ensure fuel system pressure is correct.
Check Mass Airflow (MAF) sensor.
Check spark plug condition.
Check spark plug wires.
Check ignition coil resistance.
Check engine compression.
Check for contaminated fuel.