In 2023, motor vehicles for more than 15 years will be changed to the annual first trial, which is a good thing for old car owners. Before examining the car, I took a look at the annual inspection report for 2022 and found that the measured value of exhaust gas inspection was very close to the limit. (attached picture) I heard that the tail gas emissions were more stringent this year, so I decided to clean the ternary catalysis before the annual inspection, so I studied a set of the most effective and economical method: oxalic acid immersion.
On February 19, 2023, a reliable quick repair shop near my home asked my master to help me disassemble the ternary catalysis (the man-hour fee is discussed by myself), and then diluted with the oxalic acid bought online at 1:10 and diluted with hot water of 60-70 degrees. Plug the hole below with a towel and a plastic bag in advance. (with pictures)
I took a look at the ceramic honeycomb. It’s not very dirty.
I bought three bottles of oxalic acid (500g for a few yuan each). As a result, a bottle of oxalic acid powder was enough. 500g hot water was mixed into 5000g solution, and 5L of quick ternary catalytic irrigation was filled. (hot water decomposition effect is better)
Below plug, after the oxygen sensor hole to find a screw wrapped with electrical tape to plug, like mine this ternary catalysis is not particularly dirty is only soaked for 2 hours, if a bit blocked, then soak for 5 hours. After soaking, rinse the ternary catalysis with 2 basins of water and drain the water for a few minutes. After soaking, the ceramic core of the ternary catalysis is bright silver (forgot to take pictures).
PS: it is not recommended to add ternary catalytic detergent to the gasoline tank, it is to pay IQ tax.
While soaking ternary catalysis, soak the oxygen sensor before and after cleaning with oxygen sensor cleaning agent.
Two hours later, the ternary catalysis and oxygen sensor were installed and the car was ignited. Because there is still a small amount of water in the ternary catalysis, and the temperature does not reach 400 degrees, a large amount of white smoke will be produced in the exhaust pipe. In order not to be complained by others, I drove out for 20 minutes of high speed, and the engine tried to reach 3000 revolutions. When I came back, there was no smoke in the exhaust pipe, and the exhaust was fresh.
After a few days, I prepared for last year’s trial, during which 95 # gasoline was added. Attached below is the 2023 exhaust test report, the measured value of exhaust emissions is much better than that in 2022, and the effort is worth the effort.
Fig. 1, measured value of tail gas in 2022. In 2023, motor vehicles for more than 15 years will be changed to the annual first trial, which is a good thing for old car owners. Before examining the car, I took a look at the annual inspection report for 2022 and found that the measured value of exhaust gas inspection was very close to the limit. (attached picture) I heard that the tail gas emissions were more stringent this year, so I decided to clean the ternary catalysis before the annual inspection, so I studied a set of the most effective and economical method: oxalic acid immersion.
On February 19, 2023, a reliable quick repair shop near my home asked my master to help me disassemble the ternary catalysis (the man-hour fee is discussed by myself), and then diluted with the oxalic acid bought online at 1:10 and diluted with hot water of 60-70 degrees. Plug the hole below with a towel and a plastic bag in advance. (with pictures)
I took a look at the ceramic honeycomb. It’s not very dirty.
I bought three bottles of oxalic acid (500g for a few yuan each). As a result, a bottle of oxalic acid powder was enough. 500g hot water was mixed into 5000g solution, and 5L of quick ternary catalytic irrigation was filled. (hot water decomposition effect is better)
Below plug, after the oxygen sensor hole to find a screw wrapped with electrical tape to plug, like mine this ternary catalysis is not particularly dirty is only soaked for 2 hours, if a bit blocked, then soak for 5 hours. After soaking, rinse the ternary catalysis with 2 basins of water and drain the water for a few minutes. After soaking, the ceramic core of the ternary catalysis is bright silver (forgot to take pictures).
PS: it is not recommended to add ternary catalytic detergent to the gasoline tank, it is to pay IQ tax.
While soaking ternary catalysis, soak the oxygen sensor before and after cleaning with oxygen sensor cleaning agent.
Two hours later, the ternary catalysis and oxygen sensor were installed and the car was ignited. Because there is still a small amount of water in the ternary catalysis, and the temperature does not reach 400 degrees, a large amount of white smoke will be produced in the exhaust pipe. In order not to be complained by others, I drove out for 20 minutes of high speed, and the engine tried to reach 3000 revolutions. When I came back, there was no smoke in the exhaust pipe, and the exhaust was fresh.
After a few days, I prepared for last year’s trial, during which 95 # gasoline was added. Attached to the 2023 exhaust test report, the measured value of exhaust emissions is much better than that in 2022.
KayKennan 
2 
September 4, 2024 
