What Causes Engine Shaking and Black Smoke When Accelerating?

[NorahMarie]

Car engine shaking and emitting black smoke are caused by issues with the oxygen sensor and poor ignition performance. Specific reasons include: Problems with the oxygen sensor. Symptoms such as black smoke, unstable idle, shaking during acceleration, and a feeling similar to a misfiring cylinder can be diagnosed by computer decoding. Poor ignition performance: Issues in systems like the fuel system or ignition system. To troubleshoot black smoke from the engine, check the following aspects: Whether sensors are damaged or input signals are incorrect: For example, if the air flow meter, throttle position sensor, oxygen sensor, or other critical sensors are damaged, the signals (voltage or frequency) transmitted to the computer may not accurately reflect air flow, leading to abnormal fuel supply and excessively rich air-fuel mixture. Vacuum leaks: First, measure the engine vacuum with a vacuum gauge, then sequentially inspect all air hoses for leaks.