Difficult To Start

Check for contaminated fuel.
Check fuel pressure.
Check for faulty Throttle Position (TP) Sensor.
Check for faulty coolant temperature sensor.
Check for loss of crank signal to PCM.
Check EGR system.
Check fuel pump relay and circuit.
Check for faulty in-tank fuel pump check valve.
Check ignition system.
Check for faulty Idle Air Control (IAC) operation (if equipped).
Check for incorrect EEPROM application (Stylus).
Check for faulty main (or PCM) relay.