This paper proposes a radial basis function (RBF) based approach for the fu
el injection control problem. In the past, neural controllers for this prob
lem have centred on using a cerebellar model articulation controller (CMAC)
type network with some success. The current production engine control unit
s also use look-up tables in their fuel injection controllers, and if adapt
ation is permitted to these look-up tables the overall effect closely mimic
s the CMAC network. Here it is shown that an RBF network with significantly
fewer nodes than a CMAC network is capable of delivering superior control
performance on a mean value engine model simulation. The proposed approach
requires no a priori knowledge of the engine systems, and on-line learning
is achieved using gradient descent updates. The RBF network is then impleme
nted on a four-cylinder engine and, after a minor modification, outperforms
a production engine control unit.