METHOD OF DETERMINING ENGINE TORQUE

A method of controlling a vehicle engine comprising estimating a value for the actual engine torque, comparing this with a further calculated (expected) torque value, and controlling the engine consequent to said comparing, the value for the actual engine torque being determined from the following steps: • a) from a crankshaft signal, providing a plot or signal indicative of instantaneous crankshaft speed; • b) differentiating said plot or signal indicative of instantaneous crankshaft speed with respect to time to determine acceleration values; • c) within a crankshaft/time interval, determining a maximum and a minimum acceleration value from step b); • d) determining the difference between said maximum and minimum acceleration values; • e) determining a torque value dependent on said difference from step d).