Difficult To Start When Cold

Ensure battery is fully charged.
Ensure spark plugs fire strong Blue/White spark.
Check fuel pump fuse(s).
Check in-line fuse to control unit (if applicable).
Ensure ignition timing and fuel pressure are correct.
Check fuel injectors.
Ensure timing belt is not broken.
Check ground connections on intake manifold for control unit and power stage.
Ensure ignition coil resistance is correct.
Ensure rotor, distributor and plug wires are okay.
Check ignition control unit.
Check coolant temperature sensor and connector.
Check throttle switch and connector.
Check fuel control unit.
Ensure power stage receives signal from ignition control unit.
Check airflow sensor (if applicable).