Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Starting Mode

When the ignition is first turned ON (before engaging the starter), the PCM energizes the fuel pump relay for a calibrated time (approximately 2 seconds) allowing the fuel pump to build up pressure. The PCM also checks the Engine Coolant Temperature (ECT) and Throttle Position (TP) sensors to determine the proper air/fuel ratio for starting. The air/fuel ratio ranges from approximately 0.8:1 at -40 °C (-40 °F) to 16.8:1 at 110 °C (230 °F) engine coolant temperature. The PCM controls the amount of fuel delivered by changing how long the injectors are energized. This is done by pulsing the injectors for very short times.