What Causes an Engine to Lose Power?

[Deborah]

There are many reasons why an engine may lose power. Broadly speaking, there are four main scenarios: fuel system issues; intake and exhaust system problems; electrical system malfunctions; and problems with certain engine components, such as small or poorly sealing valves, worn pistons or cylinder liners, etc. Since the engine itself consists of numerous parts, this category encompasses the most potential causes. If the fuel line is clogged, leading to insufficient fuel supply, the engine typically exhibits symptoms like reduced power and difficulty starting. Particularly at higher RPMs or under heavy load when greater fuel supply is required, restricted fuel flow can result in decreased engine power and poor performance. Fuel injector leaks or clogged spray holes that prevent proper atomization can lead to incomplete combustion after fuel injection, causing the engine to lose power. Valves are responsible for air intake and exhaust emission. Intake valves that are either too large or too small will affect performance. If the intake valve clearance is too small, the engine will suffer from insufficient air supply, leading to incomplete fuel combustion in the cylinders and reduced power output. If the valves are poorly sealed or have excessive clearance, cylinder pressure leakage may occur.