Injector Duty Cycle
What percentage of available time the fuel injectors are open. Above ~85% means the injectors are near maximum capacity.
Why it matters
Maxed injectors cannot deliver more fuel. If the engine needs more fuel than injectors can deliver, it runs lean under load.
What to look for
Below 80% is healthy. 80-85% is a warning. Above 85% is critical and indicates port injection or larger injectors are needed.
Related terms
Pressurizes fuel to ~2,900+ PSI for direct injection. When it can't keep up with demand, fuel pressure drops and the engine runs lean.
The ratio of air to fuel in the combustion chamber. Lower number = richer (more fuel). Higher number = leaner (less fuel).
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