Section 6 - Injectors and Fuel Lines - Group 06 Injectors - General Information M11 Page 6-3 Injectors - General Information The CELECT™system allows an engine to have variable timing, depending on load, engine temperature, envi- ronmental conditions, etc. The timing and fueling rate are controlled electronically. The injectors used in CELECT™ engines are electronically controlled, closed nozzle unit injectors.