Editing Fuel injection (section)

=== Metering fuel ===
The system must determine the appropriate amount of fuel to be supplied and control the fuel flow to supply this amount.

Several early mechanical injection systems used relatively sophisticated helix-controlled injection pump(s) that both metered fuel and created injection pressure. Since the 1980s, [[electronics|electronic systems]] have been used to control the metering of fuel. More recent systems use an electronic [[engine control unit]] which meters the fuel and controls the [[ignition timing]] and various other engine functions.