What are the causes of exhaust emission system failure?
3 Answers
The causes of exhaust emission system failure are mostly due to damage to the oxygen sensor in the three-way catalytic system or poisoning of the three-way catalytic converter caused by the quality of domestic fuel. If this light comes on while driving, immediately reduce speed and drive to the nearest maintenance service station for inspection. The following are the reasons why the exhaust emission fault light comes on: Quality issues: The engine has relatively high requirements for fuel quality. Poor fuel quality can lead to unclean engine cylinder interiors with deposited carbon deposits, requiring engine carbon deposit cleaning. Temperature drop: During cold starts, especially when the weather temperature drops sharply, the pollution light may come on due to the computer's temperature correction issues during startup. However, once the temperature drops to a certain level and stabilizes without fluctuations, the light will stabilize accordingly.
There are various causes for exhaust emission system malfunctions. I believe the most common issue is a faulty oxygen sensor, which monitors the oxygen content in the exhaust. If it fails, the engine control unit receives incorrect signals, leading to improper fuel mixture ratios and excessive emissions. Another frequent problem is a clogged or damaged catalytic converter, which restricts exhaust flow and causes sluggish acceleration. I've seen exhaust manifolds develop cracks, leading to air leaks that disrupt system operation. When the dashboard warning light comes on, it should be taken seriously. Delaying repairs can increase fuel consumption by over 10% and compromise driving safety. Regular maintenance checks of these components can help prevent sudden failures.
In my driving experience, exhaust faults often stem from a stuck or failed EGR valve, as the EGR system is responsible for recirculating exhaust gases back into the cylinders for re-combustion. If it becomes clogged and inoperative, tailpipe pollutants will skyrocket. Vacuum hose leaks are another culprit, allowing extra air into the engine and causing incomplete combustion. I recall that severe spark plug carbon buildup can also indirectly lead to emission issues. For prevention, I recommend regular cleaning of the throttle body and fuel system to avoid component aging caused by engine overheating after prolonged aggressive acceleration. Ignoring these issues will shorten vehicle lifespan and increase maintenance costs.
