What are the symptoms of incorrect ignition timing?
2 Answers
Incorrect ignition timing manifests as unstable idle and weak acceleration. Severe cases may prevent the engine from starting, while excessively delayed ignition can cause starting difficulties or insufficient power. 1. Overly advanced ignition timing: When starting the car, the engine turns heavily (difficult to start) with a jerking sensation. At idle, the engine shakes and may stall. There is knocking sound during rapid acceleration. After starting, during operation, the engine water temperature is high and often boils over. 2. Excessively delayed ignition timing: The engine feels sluggish, weak, or even overheats. When suddenly opening the throttle, the engine speed cannot increase accordingly, and fuel consumption rises. During rapid acceleration, the exhaust pipe may sometimes backfire.
I really noticed it when driving my old car—stepping on the gas pedal felt like stepping on cotton, the engine just roared without moving. On the highway, it couldn't pick up speed for overtaking, and the strangest thing was the exhaust pipe occasionally backfiring, making popping sounds like coughing. Later, the mechanic checked and found the ignition timing was off by a full 5 degrees. After adjusting it, the throttle response became immediate, and the acceleration push was back. This kind of problem is most easily mistaken for poor fuel quality, but in reality, idle shaking plus foul-smelling exhaust are clues. Driving like this long-term can ruin the catalytic converter and increase fuel consumption by 1-2 liters.
