Motorcycle Glossary

Fuel injector

In Turkish: Enjektör

In short

A fuel injector is the solenoid valve in fuel-injected engines that sprays pressurised fuel into the intake on command from the engine control unit (ECU).

In a fuel injection system the fuel pump supplies fuel to the injector at constant pressure, and the ECU sets how long the injector stays open based on its sensors (throttle position, air temperature, engine temperature, oxygen sensor). This keeps the mixture more precise than a carburettor in all conditions.

Symptoms of a problem

Hunting idle, misfiring, bogging when you open the throttle
Higher fuel consumption
Hard starting

Dirty fuel and long storage can clog the nozzle; injectors can be cleaned ultrasonically or replaced. Always renew the O-ring seals when refitting an injector.