What is the difference between direct injection and multi-point injection?
2 Answers
Differences between direct injection and multi-point injection: 1. Different fuel injection methods: Direct injection delivers fuel directly into the cylinder, where it mixes with air from the intake manifold before combustion; multi-point injection sprays fuel at the intake manifold, where it mixes with air before entering the cylinder for combustion. 2. Different technologies: Direct injection technology is less mature and more complex in structure; multi-point injection technology is mature and simpler in structure. Direct injection involves injecting fuel directly into the cylinder to mix with air, with advantages including lower fuel consumption, higher power output per liter, and a compression ratio as high as 12, improving power and torque by 10% compared to conventional engines of the same displacement. Multi-point injection refers to the process in gasoline engines where fuel is injected into the intake manifold, controlled by a specific timing sequence from the control program, and executed by electronic fuel injectors.
I've always been quite focused on the driving experience of cars, and the difference between direct injection and multi-point fuel injection mainly lies in how the fuel injection method affects daily driving sensations. Direct injection sprays fuel directly into the engine cylinder, resulting in more complete combustion, lower fuel consumption, and a feeling of quicker power response and stronger acceleration, especially offering better fuel economy at low to medium speeds. However, it does have its drawbacks, such as the intake valves being prone to carbon buildup, requiring a cleaning at the shop every few tens of thousands of kilometers. If not addressed, the car may start to shake and lose power. Multi-point fuel injection, on the other hand, sprays fuel into the intake port of each cylinder, where it mixes with air before entering the cylinder. This method is simpler and more stable, less prone to issues, and easier to maintain. However, it tends to have slightly higher fuel consumption and a less agile throttle response. I recommend choosing a direct injection car if you prefer fuel efficiency and that push-back feeling during acceleration, but be prepared for regular maintenance. If you're commuting in the city and want something hassle-free, multi-point fuel injection is more reliable and won't give you trouble over time.
