What is the difference between high idle speed and low idle speed?
2 Answers
The difference between high idle speed and low idle speed lies in the different rotation speeds and fuel consumption. The following is a detailed introduction about the fuel consumption per 100 kilometers of a car: 1. Overview: The fuel consumption per 100 kilometers refers to the fuel consumption of a vehicle traveling a hundred kilometers on the road at a certain speed. It is a theoretical indicator of the vehicle. The fuel consumption per 100 kilometers is the value measured by the manufacturer in an objective environment using a dynamometer installed on the chassis of the vehicle, converted into speed parameters, and then specified speed driving is used to calculate the theoretical experimental fuel consumption data per 100 kilometers of the model. 2. Others: Since most vehicles are close to the economical speed at 90 kilometers per hour, most of the theoretical fuel consumption published externally is usually the fuel consumption per 100 kilometers at 90 kilometers per hour.
I've been driving for years and find the difference between high and low idle speeds quite noticeable. High idle means the engine revs too fast in neutral, like the tachometer needle soaring above 800 RPM, sounding like a loud hum as if the car's about to take off. Low idle is the opposite, with RPM dropping below 600, causing the car to shake violently and potentially stall when starting. This difference isn't just about RPM levels—it significantly impacts daily driving. High idle drastically increases fuel consumption and is noisy, while low idle makes it hard to start at traffic lights and can even prevent the engine from firing up. Common causes include a dirty throttle body, faulty sensors, or intake leaks. I recommend regular maintenance rather than waiting until problems escalate.
