What should I do if the automobile exhaust is unqualified? Solution of unqualified tail gas

What should I do if the exhaust gas test fails in the annual review?

Although the environmental protection sign has been cancelled in the annual inspection, the exhaust gas detection has to continue, and with the strict control of environmental protection policies, the exhaust gas detection has become more and more strict. Once the vehicle's exhaust gas is unqualified, the staff will give you a notice of unqualified items in motor vehicle detection, and inform the owner to go to the repair shop for relevant maintenance before re-inspection. Then, the owner only needs to go to the outside repair shop to carry out relevant repairs before he can go online for inspection (re-queuing). When re-inspecting, he needs to bring this notice and maintenance invoice to prove that your vehicle was tested after maintenance.

Solution of unqualified tail gas

In the annual review, methane, carbon monoxide and nitrogen oxides in tail gas emissions are the focus of tail gas detection. First of all, let's understand how CH, CO and nitrogen oxides are produced in the exhaust gas. CH and CO are mainly caused by incomplete combustion in the cylinder, while nitrogen oxides are mainly caused by the high temperature in the cylinder, which leads to the combination of N2 and O2 in the air and produces nitrogen oxides. Knowing this basic knowledge, let's talk about the solutions to unqualified exhaust gas detection.

According to the test results of tail gas, the following methods can be used for simple judgment and maintenance.

1, CO, HC and NO all slightly exceeded the standard.

It may be that the spark plug gap is too large; Nozzle detects poor atomization, cylinder wear, a large amount of carbon deposit and rubber oil, three-way catalyst and oxygen sensor failure. Check the air filter, spark plug, air temperature sensor and intake pipe pressure sensor, add dual-core anti-wear repair agent and high-efficiency cleaning agent, and if it fails, clean the three-way catalytic converter with three-way catalytic converter cleaning agent.

2.CO and HC are unqualified, and NO is qualified.

It may be due to insufficient oxygen supply in the intake system, cylinder wear, carbon deposition in the cylinder, poor atomization of the nozzle, and carbon deposition in the cylinder wear. Install energy-saving wafer cleaning device for vehicles and boats, use efficient cleaning agent and add dual-core anti-wear repair agent.

3.CO and HC slightly exceeded the standard, and NO seriously exceeded the standard.

It may be that the fuel-air mixture ratio is adjusted too thinly, a large amount of carbon is accumulated in the intake system and the engine combustion chamber, and many open flames are formed in the cylinder, and the three-way catalyst and oxygen sensor fail. After using the efficient cleaning agent, the dual-core anti-wear repair agent is added for repair, and the three-way catalyst is cleaned with the three-way catalyst cleaning agent.

4.CO exceeded the standard, and HC and NO were qualified.

It may be that the engine mixture is too thick, the engine combustion is incomplete, the intake system is not smooth, the nozzle is worn, and the cylinder is seriously worn. Check the air filter, spark plug and ignition timing. After using high-efficiency cleaning agent, add dual-core anti-wear repair agent for repair.

5.CO and HC are unqualified, NO is qualified, and black smoke is emitted under heavy load.

It may be that the cylinder is seriously worn and the cylinder pressure is seriously reduced. If the self-repairing protective agent cannot effectively improve the cylinder pressure, replace the piston ring, cylinder liner, cylinder gasket, cylinder head and other parts.

6.HC seriously exceeds the standard, NO slightly exceeds the standard, and CO is qualified.

It may be due to serious carbon deposition in the cylinder, poor exhaust, aging spark plugs and air leakage in the crankcase. After using high-efficiency cleaner, it is recommended to replace high-quality engine oil and add dual-core anti-wear repair agent.