The exhaust ternary temperature is too high after Buick cleaned the throttle.

It may be because of the imbalance of oil-gas mixing, which leads to the increase of exhaust temperature.

The abnormal mixing ratio of gasoline and air in the cylinder leads to insufficient combustion of gasoline in the cylinder. When the exhaust valve is opened, some gasoline is still burning, and the exhaust temperature is bound to rise. First, the performance of the injector decreases, which leads to the coarsening of the sprayed gasoline particles, and the quality of mixing with enough air decreases, which ultimately affects the combustion speed of gasoline in the cylinder and makes the whole combustion time move backwards.

Second, the amount of air entering the engine is insufficient. This may be due to the dirty air filter, which makes the oil entering the cylinder less and less, resulting in the gasoline entering the cylinder burning (moving backwards) when not in use, and burning endlessly. At the same time, it may be because of the problem of the air flow sensor placed behind the air filter, and the collected information is unreliable. The original air intake was insufficient, but it provided false information about sufficient air intake, which made the on-board computer think that it could increase the throttle, which eventually led to the imbalance of oil-gas ratio and affected gasoline.