The idle speed of the overnight car is very high as soon as it starts, and there is a "da-da-da" sound? Why!
After parking your car overnight, you may experience an abnormally high idle speed when you start it the next day, accompanied by an abnormal "click" sound. What is the reason for this? Next, let's ** the mystery behind this.
First of all, we need to be clear about what idle speed is. To put it simply, idle speed is the minimum speed at which the engine can be kept running when the vehicle has come to a standstill. Normally, this speed should be between 700-900 rpm.
However, in some specific cases, the idle speed may be abnormally high.
The main causes of increased idle speed include:
Throttle carbon deposits: Carbon deposits can affect air circulation, resulting in insufficient engine air intake. In order to maintain normal operation, the computer system automatically increases the throttle opening, which causes the idle speed to increase.
Low engine temperature: During a cold start, the computer system temporarily increases the idle speed in order to warm up the engine quickly. As the engine temperature gradually rises, the idle speed will decrease accordingly.
Injector carbon deposits: Carbon deposits can affect fuel injection and atomization, resulting in unstable engine operation and increased idle speed.
Poor fuel quality: The use of low-quality fuel can affect the combustion efficiency of the engine, resulting in abnormal idling.
And the abnormal sound of "da-da-da" may be caused by the following reasons:
Valve train failure: including wear, loosening, or improper adjustment of valves, valve seats, valve guides, and other components.
Excessive gap between the piston and the cylinder wall: This causes the piston to collide with the cylinder wall during movement.
The gap between the connecting rod and the crankshaft is too large: the connecting rod and the crankshaft produce an impact sound during operation.
Excessive clearance between the piston pin and the connecting rod bushing can also cause an impact sound.
In response to these problems, we can take the following measures to solve them:
Regularly clean the carbon deposits on the throttle and injector to keep them in good working order.
Choose high-quality fuel and avoid damage to your engine from using low-quality fuel.
During a cold start, wait patiently for the engine to warm up and don't rush to accelerate.
Regularly inspect the clearance and wear of components such as valve trains, pistons and cylinder walls, connecting rods and crankshafts, and piston pins and connecting rod bushings, and adjust or replace them if necessary.
If the above measures cannot solve the problem, it is recommended to send the vehicle to a regular car repair shop for inspection and maintenance in time to ensure the normal operation of the engine and the safe driving of the vehicle.
In the face of the phenomenon of the overnight car idling very high as soon as it starts, and the "da-da-da" sound, we don't need to panic too much. As long as you understand the reasons behind it and take corresponding measures, you can restore your car to a healthy state!