Volvo xc60 throttle learning

Check whether the throttle valve needs cleaning. My 13 model has the same problem in winter, but there is no problem. When the time comes, the spark plug will be replaced, and the throttle will be washed when necessary, which will obviously improve the cause analysis of the car shaking when the cold car starts: the most fundamental reason for the phenomenon of shaking when the cold car starts or waits in neutral is poor combustion in the cylinder. If the combustion is not good, the power provided by the car is not enough, and the car will shake. 1. When the ignition energy is low, the first problem the car faces during cold start is low temperature. The temperature in the engine is not enough, and the temperature of fuel and lubricating oil is not enough. More fuel should be sprayed during cold start to meet the power requirements. The larger the gap between spark plugs, the smaller the ignition energy. Fuel atomization is not good at low temperature, and fuel needs high ignition energy. When the automobile is used for a long time, the ignition gap of the spark plug is easy to become larger, which leads to the decrease of ignition energy, thus affecting the power performance and making the automobile shake. In addition, the aging of ignition coil, aging of spark plug high voltage line or leakage will also lead to the decrease of ignition energy. 2. The mixing ratio is not appropriate. There is an incorrect oil-gas mixture ratio in both open-loop and closed-loop control. In a closed-loop controlled car, the minimum working temperature of the oxygen sensor is 370 degrees Celsius. If the car has just started, the oxygen sensor will not work because the temperature in the exhaust pipe is lower than 370 degrees Celsius. At this time, the ECU made a mistake in judgment, and the actuator made a mistake in controlling the oil-gas mixing and ignition time, thus reducing the power output of the automobile and causing jitter. Carbon deposition on valves and air intakes. If there is carbon deposit in the valve and air intake of the engine, ECU will make a wrong judgment, because carbon deposit can absorb a proper amount of fuel (just as water flows through the river bank and soil absorbs water). The computer actually controls the injection of 100 parts of oil and gas, but only 90 parts actually enter the cylinder (10 parts are absorbed by carbon deposits), so even if the remaining 90 parts of mixed oil and gas are fully burned, the required power cannot be achieved, and the jitter phenomenon is inevitable. 3. The working conditions of each cylinder are different. Similarly, the spark plugs of multi-cylinder machines will also have the above problems. After long-term use, the ignition gap and time control of spark plug will be different, but ECU can't diagnose this deviation and still treat it equally, which leads to practical and theoretical errors. Therefore, some cylinders generate less power, which will lead to jitter. After the engine is used for a long time, the gap between each cylinder liner and piston will be different, that is, some gaps are large and some gaps are small. In cold start, without good oil lubrication, the cylinder with large gap is easy to leak some high-temperature gas from the gap, thus reducing the power output. 4. The water temperature sensor is out of order. The water temperature sensor is one of the important bases for the computer to judge the working condition of the engine at that time. If the temperature of the engine during cold start is-10 degrees Celsius, but the sensor "tells" the computer that the temperature is 20 degrees Celsius now, then the computer will inject fuel at 20 degrees Celsius, and the amount of oil will be less, so it is natural to appear jitter. 5. Other factors. The air flow meter is dirty, resulting in a decrease in air intake; EGR (exhaust gas recirculation) valve is not working well, and exhaust gas is introduced at idle speed; The idle motor controls the bypass air inlet to adjust the air inlet. If the voltage is low, it may not work normally. The oil product is too poor to reach the corresponding calorific value, resulting in low combustion output power. The above four factors will lead to poor cylinder combustion during cold start or neutral waiting, which will lead to engine jitter. In winter, because the engine water temperature is too low, the engine starts to tremble. In order to raise the engine temperature to the ideal working temperature as soon as possible, the fuel supply system will automatically enrich the mixture, which will aggravate the engine operation, resulting in unstable engine operation and large idle jitter. Therefore, vehicles should be warmed up before driving in winter. Warm-up is the first step in winter driving, and it is also a particularly important step. Because of the low temperature in winter, lubricating oil is much more viscous than other seasons, and it is not easy to flow. Therefore, after starting the engine, the engine should be kept at about 1000 rpm, and the car should be warmed up before starting. Don't slam on the accelerator at this time, and the engine speed should not be too high. Preheating does not need to wait for the engine temperature to rise to the optimal temperature before starting, as long as the thermometer pointer starts to rise. @20 19