How To Repair Common Engine Faults

As a core component of automobiles, the engine often exhibits faults such as abnormal noise, shaking, and decreased power. Most common faults do not require complex disassembly, and mastering targeted maintenance methods can quickly solve problems and avoid the expansion of faults. This article summarizes four types of high-frequency faults, clarifies maintenance steps and precautions, and is suitable for most household and commercial engines.

1、 Fault 1: Engine idle shaking (most common)

Repair Method

First, check the spark plug. If there is severe electrode carbon deposition and excessive gap, replace it directly with a spark plug of the same specification; If the spark plug is normal, check for carbon buildup on the throttle valve, remove the throttle valve and clean it with a special cleaning agent, reset it and match it with idle speed. If it still shakes, check for clogged fuel injectors, clean them with ultrasonic waves, or check for air leaks in the intake manifold and replace the gasket.

Precautions

Avoid using inferior spark plugs. After cleaning the throttle valve, idle for 5 minutes to ensure stable working conditions.

2、 Fault 2: Engine abnormal noise (classified maintenance)

Repair Method

Valve abnormal noise (clattering sound): Adjust the valve clearance to the standard value, replace the aging valve oil seal to ensure sufficient lubrication;

Abnormal noise of timing chain (rattling sound): Check the stretching amount of the chain. If it exceeds the standard, replace the chain and tensioner, and calibrate the timing mark;

Bearing abnormal noise (dull thudding sound): Check the oil pressure. If the oil is insufficient or deteriorated, replace the oil and filter element in a timely manner. If it is severe, repair the crankshaft and connecting rod bearings.

Precautions

Before investigating the abnormal noise, avoid high-speed operation to prevent further wear of components.

3、 Fault 3: Engine oil leakage (precise leak prevention)

Repair Method

Firstly, locate the leakage point: if the valve cover is leaking oil, replace the valve cover gasket and tighten it with torque; Oil pan leakage, replace oil pan gasket, apply special sealant; The crankshaft oil seal is leaking. Replace the oil seal and check the wear of the crankshaft journal. The oil filter and drain screw are leaking. Replace the sealing ring directly and tighten it.

Precautions

Replace the seals with original parts, and tighten the bolts according to standard torque to avoid being too loose or too tight.

4、 Fault 4: Decreased power and increased fuel consumption

Repair Method

Prioritize checking the air filter element, replace it if it is clogged; Next, check the fuel filter element and replace it regularly to ensure the purity of the fuel; If black smoke is emitted from the exhaust, clean the fuel injector and throttle valve, and check if the ignition coil is faulty. Long term failure to clean carbon deposits requires engine carbon cleaning to restore combustion efficiency.

Precautions

Daily use of fuel and oil that meet the specified standards and regular maintenance can reduce the occurrence of such malfunctions.

Common engine malfunctions are often related to improper maintenance, and the core of maintenance is to "locate first, then treat the symptoms" to avoid blind disassembly. Simple faults can be operated by oneself, while complex faults (such as cylinder cracking and connecting rod damage) require professional maintenance to ensure stable engine operation after repair.