What Causes Engine Resonance for Over Ten Minutes When Cold?
3 Answers
Cold start vibration is mainly caused by carbon deposits, weak ignition, low cylinder pressure, substandard fuel, etc. Detailed causes: Excessive carbon deposits on throttle body, fuel injectors, and intake passages; When there's excessive carbon buildup inside the engine, gasoline sprayed by the cold start injectors gets largely absorbed by the deposits, resulting in an overly lean air-fuel mixture during cold starts that causes vibration; Mechanical failures in ignition coils, spark plugs, or fuel injectors leading to cylinder misfires; Insufficient fuel pressure or cylinder pressure causing power deficiency; Poor fuel quality; Damaged or excessively dirty idle control valve; Intake manifold leaks; Damaged engine mounts or cushion pads; Oxidized or low-grade engine oil with poor low-temperature fluidity, leading to inadequate cold start protection. Recommendation: It's advisable to visit a 4S shop or repair facility for inspection and maintenance to enhance the vehicle's safety performance.
I often encounter the issue of noticeable engine vibration during cold starts, which only stabilizes after more than ten minutes. The main reasons could be aging engine mounts where the rubber hardens at low temperatures and fails to absorb vibrations, improving as it softens upon warming up. It might also be due to damaged engine mounts that need replacement. During cold conditions, loose belts or poor operation of accessories like the alternator or water pump can cause resonance due to friction, which normalizes after warming up. Additionally, the catalytic converter may not function efficiently when cold, leading to poor exhaust flow and engine shaking, which resolves once the converter heats up fully. It is advisable to check if the chassis rubber components are cracked and replace them if necessary, along with regular maintenance. In extremely cold weather, higher oil viscosity results in poorer lubrication, causing more initial vibration—ensuring the use of appropriate winter-grade oil can alleviate this. Do not wait until the problem becomes severe before addressing it.
Engine cold start resonance, which takes more than ten minutes to quiet down, is quite common because the oil is thick and has poor fluidity when cold, preventing it from fully lubricating mechanical components, leading to vibrations. The situation improves as the oil thins out after warming up. If the air-fuel ratio is improperly controlled, fluctuations in mixture concentration and poor ignition due to spark plug carbon buildup can exacerbate the shaking, which stabilizes once the engine warms up. Check if the oil viscosity is suitable for the current temperature, and replace degraded oil regularly as it affects lubrication. A clogged air filter restricting airflow can also cause this issue, and replacing it can help. For prevention, avoid frequent short trips to allow the engine to warm up fully, reducing carbon buildup. Simple maintenance can go a long way.
