The brief
Mrs Hoe's 316i had a serious engine issue, a persistent check engine light that wouldn't clear and the engine not running as it should. A complete inspection and check confirmed the trouble was inside the engine, not a sensor or an external part, which means an overhaul, the engine stripped down and the worn internals renewed. An engine overhaul is the big job: the engine is removed or stripped on the car as the work calls for, the head taken off, the bottom end opened up, and every wear part inspected, the bearings, the rings, the valves, the seals and gaskets. The worn ones are renewed, the rest cleaned and checked, and the engine is rebuilt to the manufacturer's spec, then run in carefully. It's a substantial repair, but it's what brings a tired engine back rather than scrapping the car.
The diagnosis
A full inspection and a compression and leak-down check confirmed the fault was internal, the engine's wear past the point where an external fix would help. The codes and the symptoms pointed inside, and a strip-down was the only way to put it right. That's an engine overhaul: strip the engine, inspect every internal component, renew the worn parts, replace all the gaskets and seals, rebuild to spec, and run it in.
The work
The engine was stripped down, the head off and the bottom end opened up. Every wear part was inspected, and the worn internals, the bearings, the rings, the valves and the seals, were renewed with genuine BMW-spec parts, the rest cleaned and checked. New gaskets and seals went in throughout, the engine was rebuilt to the manufacturer's spec with every fastener torqued to figure, then refilled with fresh oil and coolant and run in carefully on the bench and the road. The rebuilt engine confirmed clean compression, steady running, no warning light, and proper power.
The outcome
Clean compression, a steady idle, full power, no warning light, and an engine rebuilt with fresh internals, gaskets and seals. The 316i went home with the engine overhauled. A serious internal engine fault is the big repair, but a proper overhaul brings the engine back to good health rather than the car going to scrap, and Mrs Hoe got her car back running properly.
