Electronic controller detecting oscillatory condition in combustion engine - adjusts amt. of fuel injected or timing of ignition with throttle by=passed according to fuel quality

摘要

A valve (6) in the bypass (2a) of the throttle flap (5) is opened and closed by the controller (11) in response to measurements of air intake flow (4), flap position (7), engine temp. (8), crankshaft angular position (101) and fuel refractive index (16) as a measure of octane rating. Instability is detected and corrected by an increase in injection (12) of heavy fuel, or retardation of ignition (13) for light fuel with induction of a larger quantity of air during idling. ADVANTAGE - Defective control in transient conditions is prevented with operation optimised w.r.t. differences in octane rating of petrol.