What to Do When Vehicle Exhaust NO Emissions Exceed Standards?

[KateLynn]

NO emissions exceeding standards significantly requires first cleaning the cooling system and radiator system, and even flushing the lubrication system. Here is relevant information: 1. Then install Easy Drain "One Oil", which not only reduces and removes carbon deposits throughout the engine's oil system but also greatly improves fuel combustion efficiency, allowing fuel to burn more efficiently within the engine. Carbon deposits in the oil passages, combustion chamber, three-way catalytic converter, and oxygen sensor are gradually cleaned. 2. This reactivates the purification functions of platinum, rhodium, and palladium in the three-way catalytic converter, significantly reducing the emissions of CO, HC, and NOX in vehicle exhaust. This achieves improved fuel combustion efficiency, enhanced cold-start performance, restoration of the vehicle's original power, reduced fuel consumption, extended service life of the three-way catalytic converter and oxygen sensor, and lower overall maintenance costs.

[AmaraAnn]

I was really worried when my car failed the annual inspection due to excessive NO emissions. But later I found out that 80% of the time it's caused by a clogged catalytic converter. This thing is like the car's purifier—using low-quality fuel or engine oil burning can make it fail prematurely. I quickly took the car to a professional repair shop. The mechanic used an endoscope to check and confirm if this was the issue. Replacing a new one costs around two thousand yuan, but it's worth it. Another possible cause is an imbalanced air-fuel ratio or a faulty oxygen sensor, which can also lead to excessive emissions. These issues can only be identified by reading the fault codes with an OBD scanner. To prevent this, always use high-quality gasoline and occasionally drive at high speeds to rev the engine, which helps protect the catalytic converter and extend its lifespan.

[VonKinsley]

I remember two years ago when my old Passat had the exhaust warning light on, and the NOx readings were three times higher than the standard. An experienced mechanic taught me a few practical tricks: first, check if the EGR valve is stuck. This valve is responsible for recirculating exhaust gases back into the cylinders for secondary combustion. If it's clogged with carbon deposits and can't open, it directly affects the exhaust. Next, check if the spark plugs are worn out. Delayed ignition can raise combustion temperatures, leading to more nitrogen oxides. Finally, inspect the coolant temperature sensor. Incorrect readings can cause the engine to misjudge operating conditions. These simple troubleshooting steps saved me unnecessary expenses. If all else fails, try filling up with higher-octane gasoline and taking a highway drive—sometimes the issue just improves.

[LawsonMarie]

Excessive exhaust emissions directly threaten driving safety. I've personally witnessed inspection stations detaining vehicles that failed emissions tests. Excessive nitrogen oxide levels usually indicate incomplete engine combustion. Not only will fuel consumption increase by 30% if left unrepaired, but the most dangerous consequence is when the catalytic converter fails - the exhaust pipe can accumulate carbon deposits, turn red, or even spontaneously combust. It's recommended to stop immediately for inspection, focusing on four key components: the oxygen sensor probe, exhaust gas recirculation valve, fuel injection system, and air flow meter. Never attempt to bypass the issue by disconnecting the malfunction indicator light, as inspection stations now have real-time OBD monitoring.