Sequential Fuel Injection

Fuel injection system can operate in one of 2 injection modes: simultaneous or sequential. In simultaneous injection mode, fuel is injected into all cylinders at same time. In sequential injection mode, injectors are triggered in spark plug firing order. Fuel injection operates in sequential mode under most conditions. Fuel injection will shift from sequential to simultaneous mode during starting and when ECM is operating in fail-safe mode. For more information on fail-safe modes, see appropriate SELF-DIAGNOSTICS article.