Engine Surges

Using scan tool, perform actuator tests for fuel injectors.
Check wiring between injectors and ECM/PCM.
Check ignition timing.
Using scan tool, check closed throttle position switch (if applicable), IAT sensor, BARO sensor, ECT sensor, TP sensor, EGR solenoid and front and rear HO2S values.
Using scan tool, perform actuator test for EGR solenoid.
Check fuel pressure.
Check for vacuum leaks.
Check PCV valve operation.
Check for clogged injectors.
Check ignition system.
Check EGR system.