A Multi Input Multi Output (MIMO) fuzzy estimator variable structure control (VSC) which containing an on-line controller coefficient tuned with the aim of a fuzzy back stepping algorithm. Satisfactory trajectories tracking among the internal combustion engine (IC engine) air to fuel ratio and the preferred input is certified in this paper. The fuzzy controller deployed in developed fuzzy estimator variable structure controller works using Lyapunov fuzzy inference system (FIS) with least model based rule base. Function among variable structure function, error and the error’s rate is represented by model. The outputs show fuel ratio. The fuzzy back stepping tactic is an on-line variable structure function fixing with the aim of an adaptive approach. MIMO fuzzy estimator and VSC performance with an on-line fuzzy back stepping algorithm (FBAFVSC) tuned with the aim of controller coefficient is confirmed using a comparison with VSC and planned approach. Simulation outputs indicate excellent presentation of fuel ratio in attendance of ambiguity and exterior annoyance.