What Causes an Unstable Engine Tachometer?

[StAbel]

Generally, it is caused by factors such as air intake system and valve leaks, excessive carbon buildup on the throttle body and intake manifold, and inaccurate idle air intake. Engine idle instability usually refers to idle speed fluctuating beyond the expected range of ±20r/min or experiencing severe speed fluctuations. It is recommended to visit a 4S dealership to diagnose the specific cause. Relevant information about idle is as follows: Introduction: Idle is an operating condition of a car, referring to the engine running in neutral gear. The engine speed during idle is called idle speed. Idle speed can be adjusted by modifying the throttle opening size, among other methods. Idle essentially means the engine is "producing power without doing work." Driving idle: When the car is in gear, without pressing the accelerator pedal or releasing it during driving, maintaining the minimum throttle opening, the engine speed matches the parked idle speed, which is referred to as driving idle.