Injector Dead Time: The Small Number Behind Stable Fueling
Correct injector characterisation is what lets one fuel model behave consistently from hot idle to a charging alternator.
Commanded time is not all fuel flow
An injector needs time to build magnetic force and physically open. The ECU adds this non-flowing delay to the calculated pulse width. Because the delay changes with battery voltage and fuel pressure, a single guessed value can create a mixture that moves whenever fans, lights or charging load change.
Small pulse widths expose bad data
At high load, dead time is a small part of the total pulse. At idle, it can be a large percentage. That is why poor injector data often shows up as unstable idle, difficult starting or cylinders that respond differently to voltage changes even when the main fuel table appears sensible.
Use matched data and verify the result
Start with characterisation data for the exact injector, pressure differential and driver type. Then verify lambda behaviour while voltage changes in a controlled way. Correct dead-time data should reduce the amount of correction the tune needs rather than becoming another table used to hide a mechanical or electrical issue.
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