Wei Chai engine made an abnormal squeak.

1, engine knock. It is a kind of white sound similar to metal percussion, which can also be said to be cylinder percussion. The causes of failure can be divided into three types: A. The fuel is unqualified, using inferior fuel or low-grade fuel. B, engine timing control error, such as ignition advance angle is too large. , readjust the timing. C. If there is too much carbon deposit inside the engine, you can first try the carbon deposit cleaning effect by disassembling the engine or pulling the engine at high speed, otherwise you can only disassemble the engine to clean the carbon deposit. Generally, more serious situations are often accompanied by more serious situations of burning engine oil. 2. Abnormal valve sound. After the car stops, the engine rattles, which is the sound of the valve door, especially after the car stops cold, because the oil pressure hasn't gone up and the valve hasn't been lubricated in place, and it will naturally be fine after a while. This will happen if your car has been parked for a long time. If this sound keeps ringing, it may be that the valve clearance is too large or the camshaft leaks oil, so it is necessary to adjust the valve clearance or replace the relevant oil seal. It is also possible that the engine oil used is unqualified. For example, a car with a high mileage uses thinner engine oil, which can be eliminated by changing the engine oil (see how to choose the appropriate engine oil for details). 3. Engine "backfire" failure. There is a "poop-poop" sound when the car slows down to collect oil, which may be the engine "backfire" fault, that is, the engine "shoots" at ordinary times. Excessive valve carbon deposition or incorrect valve timing will produce abnormal noise. Remove the carbon deposit on the valve or adjust the valve timing. This engine is short of cylinders. If a cylinder doesn't work, the engine will lose its balance and produce abnormal noise, accompanied by serious engine jitter, insufficient power and other faults, which may be the ignition module, spark plug and fuel injector. Just replace the corresponding accessories. 5. Engine timing adjustment error. People who have just replaced the timing belt should pay special attention to the fact that the replacement of the timing belt is more complicated. If there is a mistake when replacing the timing belt, such as incorrect timing adjustment, there will probably be a serious metal knocking sound inside the engine, which will directly affect the overhead valve (valve tilt). At this time, only valves and other related accessories can be replaced, and the engine needs to be disassembled. 6. The oil has not been changed for a long time. There is no special regular sound, but I feel that the engine sound is obviously getting louder. It is very likely that the oil is dirty and deteriorated. After replacing the new oil, the noise of the engine can be obviously felt to decrease. 7. The plastic parts in the engine compartment are loose, such as the plastic cover above the engine, the engine intake pipe, the air cleaner housing, etc. , as well as screws and buckles for fastening related accessories. 8. Abnormal sound of engine belt. It is a rather annoying "squeaking" sound, such as generator belt, air conditioning belt, steering booster pump belt and so on. Either the belt is too loose or too tight, or the belt is aging. Adjust the belt tightness, butter the belt, or replace the belt. 9. Abnormal sound of bearing. The regular "buzzing" sound is probably the abnormal noise of bearings, such as generator bearings, tensioners and idlers. (Generally, wheel-shaped rotating objects have bearings), so only relevant accessories need to be replaced. 10, starter failure. There is a "squeaking" sound when the engine starts, and sometimes it feels difficult to start. This is a starter fault and needs to be replaced. 1 1, water pump failure. Whether the water pump is damaged, such as water leakage and blockage. There will be a "buzzing" abnormal sound, which mostly occurs over 60,000 to 80,000 kilometers. Just replace the water pump and antifreeze. 12, the problem of the engine foot pad, there is rubber in the foot pad, which is easy to age after a long time. The machine foot pad has the function of supporting the engine. Just replace the machine foot pad. 13, engine lower guard plate is loose. This is also a common problem, especially when the metal guard plate is installed in the later stage, it is likely that the assembly is not good and the screws are loose, which can be solved by adjusting and fastening.