The present invention relates to a powertrain control system (1) for a motor vehicle. The vehicle comprises an internal combustion engine (5) and an adjustable suspension system (9) operable in accordance with first and second ride height settings, said settings being associated with respective first and second vehicle ride heights. The powertrain control system (1) comprises a stop/start controller (11) for issuing an engine stop request signal and an inhibitor (15) for inhibiting operation of the stop/start controller (11) in dependence on a selected ride height setting.