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Manual transmissions dominate the Indian market for their obvious benefit of low cost and higher mechanical efficiency resulting in higher fuel economy. Synchronizer system in manual transmission enables smoother and quieter gear shifting. Synchronizer ring is the key element which provides the necessary frictional torque to synchronize the speed of gear and sleeve for smooth shifting. During vehicle running, synchronizer rings are free to rattle inside the indexing clearance. High engine torsional excitation and low clutch dampening can result into increased fluctuation of the input shaft of transmission. High fluctuation or lower contact area of synchronizer ring can lead to damage on the index area. This damage may cause hard gear shifting and gear shift blockage in case of extreme damage.

Various emission and fuel economy norms for passenger cars have been introduced by the government worldwide. In India, meeting each revision of the Bharat Stage (BS) emission standards and Corporate Average Fuel Economy (CAFE) norms is challenging, and requires the incorporation of new technologies into IC engines. One such technology used in gasoline engines is Exhaust gas recirculation (EGR). The entry of dust particles into the EGR system makes it vulnerable to malfunction. One such fleet validation challenge of EGR valve malfunction has been addressed in this study, where the EGR valve became stuck due to dust entry, leading to engine hunting and stalling. The approach followed for the issue resolution demonstrates a method of developing an EGR valve controller for simulating the failure on a bench setup. The controller setup was built around a microcontroller chip that accurately operated the valve with similar logic to that of the vehicle ECU.