In order to study the influences of different exhaust thermal management schemes on the performance and emission characteristics of diesel engines, the thermal management scheme that can meet the DPF regeneration temperature requirements and has better performance was selected for different operating conditions. The effects of intake and exhaust throttling, and post injection on the exhaust temperature, specific fuel consumption rate, and pollutant emissions of automotive diesel engines were studied under the operating conditions of low idle from 800 r/min to 1 000 r/min and low-to-medium load at 1 200 r/min by using diesel engines and after treatment systems as research objects. The results show that either intake/exhaust throttling schemes can achieve the required exhaust temperature for DPF active regeneration at low-to-medium loads of 1 200 r/min. Under low idle conditions, a combination of intake/exhaust throttling and in-cylinder post injection is necessary to meet the DPF active regeneration temperature target. At the minimum idle speed of 800 r/min, using exhaust throttling combined with post injection can increase the maximum exhaust temperature to 254 ℃. At the same exhaust temperature, the exhaust throttling scheme yields lower fuel consumption rate and NOx emissions under medium load at 1 200 r/min. As the load rate decreases, the fuel consumption and NOx emissions of intake/exhaust throttling schemes become comparable. Under low load of 1 200 r/min, the intake throttling scheme offers superior specific fuel consumption and NOx emission by comparing to exhaust throttling scheme, which decreases by more than 12% and 32% respectively. However, the intake throttling scheme performs worse in controlling smoke and THC emissions. Under idle conditions, the intake throttling with post injection scheme produces approximately twice the smoke and THC emissions of the exhaust throttling with post injection scheme at the same exhaust temperature. Furthermore, the advantage of exhaust throttling scheme over the intake throttling scheme in reducing smoke and THC becomes more pronounced as the post injection quantity increases. Under all tested conditions, the exhaust throttling scheme can achieve more favorable excess air coefficient and intake manifold pressure at the same exhaust temperature compared to other schemes.