The idle speed of Civic is unstable after changing the throttle.

After the throttle is cleaned, the idle speed is unstable. Some new cars, especially direct injection cars, have black exhaust pipes. This does not mean carbon deposition, but it must mean poor combustion. If the vehicle is so dark for a long time, there will be many other serious problems, such as burning engine oil, which can not waste engine oil and accelerate the aging of various accessories. Many unsolvable places are recognized as common problems, and many unsolvable problems are collectively called common problems. If there are problems, there are solutions. If there is a contradiction, there is a solution procedure. You can add two fuel additives to the fuel tank. After running two boxes of oil, the oil circuit will be clean and will not shake.