What are the reasons for body shaking and engine warning light coming on?
2 Answers
The reasons for body shaking and engine warning light coming on are as follows: 1. Carbon deposits on valves and intake passages: When severe carbon deposits form on the intake and exhaust valves and intake passages, the fuel injected by manifold injection engines can be partially absorbed by the carbon deposits. This results in a discrepancy between the actual fuel entering the cylinder and the amount preset by the ECU. The energy released after combustion of the mixture cannot meet the power demand, leading to shaking. 2. Deviation in cylinder conditions: When the gap between the cylinder liner and piston increases, high-temperature gases can easily leak through the gap during cold starts due to insufficient oil lubrication, reducing power output. 3. Malfunction of the water temperature sensor: The water temperature sensor is one of the important bases for the computer to determine the engine's operating conditions. If the engine's cold start temperature is -10°C, but the sensor "tells" the computer "the current temperature is 10°C," the computer will inject fuel based on the 10°C condition, resulting in insufficient fuel and shaking. 4. Unstable oil pressure: Abnormal fuel pump supply pressure or incorrect and poor performance of the intake pressure sensor can cause body shaking. 5. Fuel quality issues: When the fuel does not meet the standard, combustion cannot achieve the corresponding heat value, resulting in lower power output. In addition, incorrect fuel grade or poor fuel quality can also cause engine shaking.
I've been driving for over a decade and have encountered several instances of car body shaking with warning lights on, which can be quite dangerous. The most common cause is issues with the ignition system. For example, worn-out spark plugs or faulty ignition coils can cause certain cylinders to stop working, leading to engine imbalance and shaking. At the same time, sensor failures, such as those in the crankshaft position sensor or oxygen sensor, can trigger warning lights. Fuel system problems, like clogged fuel injectors or insufficient fuel pump pressure, can also cause the engine to 'starve' and shake violently. Poor electrical connections or blown fuses might be the hidden culprits as well. I remember one winter when the engine shook badly during a cold start, and the warning light came on. After towing it to the repair shop, they found the ignition coil had failed. After the repair, the car ran much smoother. My advice is not to wait—take it directly to a professional shop for inspection. At most, you can check the fuse box yourself to prevent minor issues from turning into major accidents.
