Engine Difficult to Start When Cold
1. Defective ECU.
2. Open or shorted fuel injector circuit.
3. Defective injector.
4. Defective fuel pump main relay.
5. Poor fuel pump ground.
6. Ice in fuel line.
7. Clogged fuel filter.
8. Stuck air bypass valve in fast idle mechanism.
9. Open or shorted crank angle sensor circuit.
10. Defective crank angle sensor.
11. Open or shorted coolant temperature sensor circuit.
12. Defective coolant temperature sensor.
13. On High Altitude models, open or shorted atmospheric air pressure sensor circuit.
14. Defective EGR control system.
15. Defective ECU.