What causes low idle speed and shaking when the air conditioner is on in a Honda CR-V?

[ValeriaLee]

Reasons and solutions for idle shaking in Honda CR-V: 1. Severe engine carbon buildup: The most common cause of car shaking is excessive carbon buildup in the throttle body or fuel injectors. When there is too much carbon inside the engine, the gasoline sprayed by the cold start injector is largely absorbed by the carbon deposits, resulting in an overly lean air-fuel mixture during cold starts and making it difficult to start. In this situation, the car will only start easily once the carbon deposits are saturated with gasoline. After starting, the gasoline adsorbed on the carbon deposits is drawn into the combustion chamber by the engine's vacuum, making the air-fuel mixture too rich. The constantly fluctuating air-fuel mixture causes idle shaking after a cold start. The solution is to clean the fuel system and check if the idle speed control valve has carbon buildup, which should be cleaned if necessary. 2. Ignition system issues: Check the condition of the spark plugs, high-voltage wires, and ignition coils. Poor performance of the ignition system or weak sparking from the spark plugs can also lead to this type of problem. The solution is to check if the spark plugs have excessive carbon buildup and replace them if necessary. 3. Unstable fuel pressure: If you have already cleaned the engine carbon deposits, throttle body, replaced gaskets, and spark plugs but still notice shaking at idle, it is recommended to visit a 4S shop to check the fuel supply pressure and the intake pressure sensor. Abnormal fuel pump pressure or incorrect readings and poor performance of the intake pressure sensor can cause the car to shake. The solution is to check the fuel pressure and replace components if necessary. 4. Aging engine components: Car shaking can also be related to aging engine mounts. Engine mounts act as the engine's vibration damping system, absorbing minor vibrations during operation. If the engine mounts are faulty, these vibrations will be transmitted to the steering wheel and the interior, causing shaking at idle speed, and they need to be replaced.