Is engine shaking related to gasoline?
3 Answers
Engine shaking is related to gasoline. Using lower-octane gasoline can cause knocking, which leads to engine shaking. It is recommended to remove the fuel tank and drain the gasoline. The causes of engine shaking include: 1. Low cylinder pressure—if one cylinder is not functioning properly, it can result in a misfire; 2. Carbon buildup and oil deposits clogging the throttle valve, idle valve, or intake ports over time, leading to poor airflow and unstable idling or shaking; 3. Clogged fuel injectors—the injectors in fuel-injected vehicles are critical components, and deposits in gasoline can block the injector nozzles, causing uneven fuel distribution among cylinders and resulting in engine shaking; 4. Abnormal coolant temperature; 5. Broken high-voltage wires; 6. Faulty spark plugs; 7. Dirty air filter.
Last time I drove my old Jetta, I encountered a similar situation where the engine was shaking like it was dancing disco. After checking for a long time, it turned out to be an issue with the gas station—the batch of gasoline had excessive impurities. A professional mechanic explained that low-quality gasoline can cause uneven combustion, especially when there's too much water or impurities clogging the fuel injectors, leading to unsynchronized cylinder operation and shaking. Later, I switched to 95-octane fuel from reputable stations and added a bottle of cleaner every 5,000 kilometers to remove carbon deposits, and the symptoms disappeared. Now, I’ve developed the habit of checking gas station qualifications when refueling, since repairing fuel injectors once costs enough to buy half a year’s worth of good fuel.
Back when I worked on cars, I encountered quite a few cases of engine shudder caused by gasoline issues. Two key factors matter most: whether the fuel octane rating matches the engine's compression ratio, and the freshness of the fuel. I've seen over a dozen cases where using 92-octane fuel caused knocking, destabilizing piston movement and resulting in shaking. Additionally, gasoline that's stored too long oxidizes and deteriorates, with gum deposits clogging fuel injectors being even more common. My advice: check your manual to confirm the correct octane rating, and don't keep gasoline for more than two months. If the engine still shudders after fresh fuel, it's more practical to check spark plug gaps or ignition coil issues.
