What are the symptoms of a faulty carbon canister purge valve?
2 Answers
The symptoms of a faulty carbon canister purge valve: 1. Difficulty starting the engine, and it is very prone to stalling; 2. Increased fuel consumption, with a noticeable gasoline smell inside the car; 3. Irregular engine idle speed, fluctuating between high and low, and lack of power during acceleration. After the engine starts, the idle speed fluctuates rhythmically between high and low, and the car lacks power during acceleration; 4. Abnormal noises when the vehicle is in motion. After the carbon canister stores gasoline vapors, when the engine starts again, the solenoid valve installed between the activated carbon canister and the intake manifold opens. The gasoline vapors in the activated carbon canister are drawn into the cylinder by clean air under the vacuum of the intake pipe to participate in combustion.
A few days ago, my car's check engine light came on, and I felt the whole body shaking at idle. The ride was particularly rough, and there was a strong gasoline smell after parking. After searching online, I found out it was an issue with the carbon canister purge valve. This component mainly controls the fuel tank's vapor recovery system, preventing gasoline odors from escaping and polluting the air. When it fails, the engine may misjudge, leading to unstable idling, occasional stalling, or difficulty starting—especially when the engine is hot. If left unrepaired for a long time, fuel consumption may increase, emissions may exceed standards, and in severe cases, it could affect the pass rate of exhaust tests. I usually enjoy tinkering with car repairs, but this time I didn't dare to touch it and went straight to a professional shop to replace the valve. It only cost a little over 300 yuan, and the car immediately ran smoothly again. I recommend that owners check for unusual odors or vibrations as soon as they appear to avoid bigger problems down the line.
