Why does the Envision shake at idle when the air conditioning is on?
2 Answers
There are several reasons why the Envision may shake at idle when the air conditioning is on, including carbon buildup in the throttle body. Below are the specific causes of the Envision's idle shaking when the air conditioning is on: 1. Carbon buildup in the throttle body: Carbon deposits can obstruct the engine's air intake, causing the engine to struggle or barely manage to power the compressor, resulting in idle shaking. 2. Excessive throttle angle: This can lead to too much air intake, causing the engine to shake and lack acceleration power during startup. 3. Issues with the ignition system: For example, poor spark plug performance can lead to unstable idle. Below is some information about car idling: 1. Car idling: Refers to an operational state. When the engine is running without load, it is called idling, meaning the car is in neutral gear. The engine speed during idling is referred to as the idle speed. 2. Adjustment: The idle speed can be adjusted by modifying the throttle opening size, among other methods.
As an Envision owner who has driven the car for four or five years, I’ve encountered the issue of idle shaking with the AC on a few times—it’s quite common. The main reason is the sudden increase in engine load when the AC compressor kicks in. Factors like carbon buildup blocking the throttle body (affecting airflow), aging spark plugs with weak ignition, and the engine’s inherently low idle power can make it struggle to cope, leading to shaking. If the engine mounts are loose or the rubber cushions are worn out, failing to absorb vibrations, the shaking becomes more noticeable. My advice: start with simple checks—listen for abnormal engine sounds at idle, sniff for foul exhaust smells—then try cleaning the throttle body or replacing the spark plugs yourself. Don’t ignore it, as worsening shaking can damage the engine. It’s safer to visit a repair shop early for a diagnostic scan, which might also save you some fuel costs.
