Posted on 7/31/2026
When an engine runs rough, burns oil, and loses compression, it is no longer a small comfort issue. Those symptoms usually mean the engine is having trouble sealing, breathing, firing, or controlling oil the way it should. The car may still drive, but it starts feeling weaker, dirtier, and less dependable. This kind of problem can sneak up slowly. First, the idle feels uneven. Then the oil level drops between services. Later, the exhaust smells different, the engine feels tired, or a compression test shows one cylinder is weaker than the rest. By that point, the concern is usually deeper than one worn spark plug. Why Compression Is So Important Compression is the pressure the engine builds inside each cylinder before the spark plug fires. The piston moves upward, the valves close, and the air-fuel mixture is squeezed tightly so it can burn with force. That controlled burn is what makes power. If a cylinder cannot hold compression, it cannot contribute properly. The ... read more