What are the differences between National III and National IV?
2 Answers
National III emission standards and National IV emission standards differ primarily in the stricter requirements for vehicle pollutant emissions. Differences: The National III emission standard was proposed in 2006 and implemented nationwide on July 1, 2007. It is equivalent to the Euro III emission standard, but compared to Euro III, National III places more emphasis on the emission standards for vehicles at -7 degrees Celsius. Additionally, new vehicles are required to be equipped with an On-Board Diagnostics (OBD) system. The National III engine incorporates improvements to the internal structure of the National II engine, including components such as the combustion chamber and intake/exhaust passages, exhaust manifold, valves, camshaft, pistons, and corresponding auxiliary mechanisms. The upgraded National III engine features higher precision in its components without affecting performance. Upgrade to National IV: Three years later, the National IV emission standard was implemented nationwide on July 1, 2010, representing an upgrade from the National III standard. It reduced pollutant emissions by approximately 50%. Currently, the National VI standard is gradually being rolled out across China, and many regions have already issued bans on vehicles meeting the National III emission standards.
National III and National IV are mainly different versions of automobile emission standards, and as a car owner, I have personal experience with this. The National III standard was implemented around 2007, and the emissions were noticeably higher when driving, especially in urban areas where you could sometimes smell exhaust fumes when parked. After switching to National IV, the emission control improved significantly—the car became cleaner and quieter, saving some fuel costs on long trips and reducing noise considerably. Many major cities now restrict National III vehicles from entering specific zones. For example, when I lived in Beijing, only National IV or higher vehicles could freely drive within the Third Ring Road; otherwise, you'd face a fine of several hundred yuan. If you're still using an old National III car, I'd suggest considering an upgrade sooner rather than later—don't wait until restrictions hit to realize the hassle. In the long run, National IV models might have slightly higher maintenance costs, but the environmental subsidies and savings from avoiding fines make it worthwhile, not to mention the peace of mind and comfort while driving. Overall, National IV is an improved version of National III, pushing the automotive industry toward greener practices while benefiting car owners as well.
