The power generation of an exhaust TEG (thermoelectric generator) depends on heat energy and thermoelectric conversion efficiency. However, there are compatibility problems among TEG, CC (catalytic converter) and muf (muffler). The present work tried to vary the installation position of TEG and propose three different cases. Case 1: TEG is located at the end of the exhaust system; case 2: TEG is located between CC and muf; case 3: TEG is located upstream of CC and muf. Simulation and experiment were developed to compare thermal uniformity and pressure drop characteristics over the three operating cases. From the simulation and experiment, heat exchanger in case 2 obtained more uniform flow distribution, higher surface temperature and lower back pressure than in other cases. At the same time, the CC and muf could keep normal working in case 2, providing a theoretical and experimental basis for the exhaust gas waste heat recovery system.