What is the reason for black smoke coming out of the SsangYong Actyon's fuel injector after cleaning?
3 Answers
The reason for black smoke coming out of the SsangYong Actyon's fuel injector after cleaning may be incorrect ignition timing or an overly rich air-fuel mixture. Incorrect ignition timing: This can also cause incomplete combustion of the air-fuel mixture; or if a few cylinders in the engine are not working, a small amount of black smoke may be emitted. If the engine's exhaust pipe emits a small amount of black smoke accompanied by a rhythmic "popping" sound, it can be determined that a few cylinders are not working or the ignition timing is incorrect. The non-working cylinder can be identified using the cylinder cut-off method, or the ignition timing can be checked and adjusted. Overly rich air-fuel mixture: This means the air-fuel mixture in the cylinder has an excessively low air-to-fuel ratio, leading to incomplete combustion. Some fuel decomposes into free carbon at high temperatures and is emitted from the exhaust pipe, forming black smoke. If the engine's exhaust pipe emits a large amount of black smoke accompanied by a backfire sound, it can be determined that the air-fuel mixture is too rich.
I feel that it's quite common for the SsangYong Actyon to emit black smoke after cleaning the fuel injectors, mainly due to improper handling during the cleaning process. For example, if the fuel injectors are not sealed properly during installation, it can cause fuel leakage. Excessive fuel injection leads to an overly rich air-fuel mixture, resulting in incomplete combustion and black smoke. Another possibility is that cleaning agent residue wasn't completely removed, affecting normal fuel injection. Additionally, if the needle valve or coil of the fuel injector is damaged during cleaning, it can cause uncontrolled fuel supply. I recommend checking immediately whether the injector's mounting screws are loose and inspecting the air filter for blockages. Black smoke not only increases fuel consumption but also damages the engine. It's best not to delay—visit a professional repair shop as soon as possible to diagnose the fuel system parameters with a diagnostic tool to prevent further deterioration.
I've experienced similar situations before. Black smoke after cleaning the fuel injectors is mostly caused by improper cleaning operations, such as not completely removing carbon deposits in the fuel system, leading to imbalanced fuel injection after cleaning. When the air supply can't keep up, incomplete fuel combustion results in black smoke. Another common reason is that the fuel injector itself gets scratched or deformed during cleaning, causing poor fuel atomization, which makes the air-fuel mixture too rich. By the way, if the ECU settings aren't updated to adapt to the new condition, it might mistakenly command excessive fuel supply. When I encounter this, I usually try restarting the vehicle and taking a short trip first to see if the problem disappears. If the smoke persists, don't attempt DIY repairs to avoid accidents - it's best to visit a professional shop to adjust the ignition system and fuel injection pulse width.
