Symptoms of a Faulty Exhaust Valve?
2 Answers
Exhaust valve damage can cause engine shaking or even stalling during idle. If the exhaust valve is faulty, some exhaust gases will enter the engine's intake manifold during idle, leading these gases to participate in combustion within the combustion chamber. This results in an overly lean air-fuel mixture, causing unstable idle or stalling. The exhaust valve, also known as the Exhaust Gas Recirculation (EGR) valve, connects the intake manifold and the exhaust manifold. It controls the degree of valve opening via a vacuum tube, thereby regulating the amount of exhaust gas entering the intake manifold. The exhaust valve contains coolant, which helps lower the temperature of the exhaust gases. When the vehicle's exhaust valve malfunctions, the engine's fault indicator light will illuminate, prompting the owner to visit a repair shop or 4S dealership for inspection.
I've been driving for twenty years, and the symptoms of a bad PCV valve are too obvious: the car idles like it's got Parkinson's, frequent surging at red lights, and nearly stalling several times. Accelerating is painfully slow, like running with chains dragging, and fuel consumption on highway climbs is 20% higher than usual, making my wallet cry. Later, during inspection, it was found that the valve was stuck, causing uneven air intake—any longer and the engine could be ruined. Usually, paying attention to idle stability and fuel consumption changes can help catch it early; don't wait for a small issue to become a big problem. By the way, regularly cleaning the intake pipe can prevent carbon buildup—it's pretty hassle-free.