ICE-38 — Engine Start

ASSUMPTION — This lesson covers the start process conceptually; specific start timings are not given.

In this lesson you will learn:

• The start stages
• The fuel/ignition strategy
• The starter motor and synchronization

1. The Start Process

Start begins with cranking: the starter motor spins the crank; the ECU establishes cylinder synchronization from the position sensors; then the first injection/ignition occurs and the engine runs on its own.

FACT — The ECU must establish synchronization from crank and cam position before it can fuel/spark the correct cylinder at the right time.

2. First Ignition and Rich Mixture

FACT — When cold, fuel vaporization is weak, so a temporarily richer mixture is used at start; it normalizes as the engine warms (ICE-39).

3. Starter Motor

FACT — The starter provides the initial mechanical energy to spin the crank and disengages once the engine runs. Modern start-stop systems use fast, frequent-restart-capable starters/integrated solutions.

4. Summary

• Start: crank → sync → first ignition → stable running.
• Synchronization is essential for correct timing.
• Rich mixture is used when cold.
• The starter provides the initial spin.

5. Sources

• Bosch, Gasoline-Engine Management and Diesel-Engine Management

Next Lesson

• ICE-39 — Cold Start.