Ford Focus RS

The Volvo-derived 2.5T suffers turbocharger bearing damage when oil changes are neglected. High boost pressure with spirited driving accelerates wear. Nitrous and chip tuning significantly increase the risk.

Symptoms: Boost drops to ~0.3 bar, power loss, whistling from the turbo area, oil loss at the turbo

The highly stressed 2.5T can suffer head gasket failure when overheated (coolant loss from turbo damage). Repair costs are very high. Check coolant level regularly, especially after turbo failure.

Symptoms: White smoke from the exhaust, coolant level drops, coolant smell inside the cabin

The 2.5L five-cylinder turbo is prone to cylinder wall cracks, especially after coolant loss from split hoses. Coolant mixes with engine oil, causing bearing damage. Complete engine replacement is often the only economic option.

Symptoms: Milky emulsion on the dipstick, white steam from the exhaust, rapid coolant loss, overheating warning

A split coolant hose causes the level to drop unnoticed. Result: overheating and cylinder wall cracks — identified by the milky residue on the dipstick. A used replacement engine is more economical than a cylinder head repair.

Symptoms: Milky emulsion on dipstick or oil filler cap, coolant loss without visible external leak, overheating warning, white exhaust smoke

Early Focus RS Mk2 suffered misfires that burst the plastic plenum chamber. Ford addressed this with an ECU remap. On modified vehicles an aluminium replacement is recommended.

Symptoms: Loud bang from the engine bay, immediate power loss, intake air leak, EGR fault codes

The 2.5 Turbo Duratec in the Focus ST and Mondeo ST tends to fluctuating boost pressure from a worn or leaking wastegate diaphragm. Boost instability appears from 80,000 km; bearing damage follows with continued use.

Symptoms: Irregular, fluctuating boost on full-throttle acceleration, overboost fault codes, occasional power drop

On the highly stressed 2.5 Turbo Duratec the crankcase breather blocks with deposits. Pressure builds up, forcing oil past the shaft seals and encouraging oil loss and turbocharger damage.

Symptoms: Oil traces at the air filter box, smoke from the oil filler cap, increased oil consumption, oil leaks at shaft seals

Sticking or leaking injectors on HUBA engines cause misfires under boost. Affected cylinders can suffer piston damage through an over-rich mixture. More prevalent from 80,000 km.

Symptoms: Juddering and stumbling on full throttle, lean misfire codes P0300–P0304, fuel smell from the exhaust

The standard clutch lasts roughly 60,000–70,000 km with spirited use. Replacement including the flywheel takes over five hours. Track use brings the interval much earlier. The RS500 with 350 hp wears it faster still.

Symptoms: Clutch slip under kickdown in high gears, pedal travel changes, smell of burning clutch after spirited driving

Despite full galvanising, sills and wheel arches rust heavily, especially at the junctions between the wing and the bumper. The tailgate rusts under the roof spoiler when water ingresses.

Wheel bearing failures frequently noted in inspection reports, especially from 2010 model year. Track rods and suspension components wear above average. Control arm bushes and lower arms fail prematurely.

Plastic thermostat housings are prone to cracking and coolant loss. Coolant temperature can become unstable; in the worst case the engine overheats.

The brake pressure sensor in the ABS block corrodes and cannot be replaced individually — the entire ABS unit must be swapped. Primarily affects vehicles up to model year 2007.

Up to model year 2007, water accumulates at the junction between the rear bumper and wheel arch, leading to rust. Ford had to carry out multiple repaints. Check carefully before buying.

Ford does not supply an individual wheel bearing — only the complete hub (approximately 290 EUR). Lower RevoKnuckle needle bearings can seize. Press-fitting requires specialist tools. High front tyre wear accelerates deterioration.

Wheel arch edges are almost universally affected without cavity wax treatment. Water penetrates through rear light seals and spoiler fixings into the boot floor, which then corrodes from the inside.

ABS cables chafe on suspension components, ranging from a simple warning light to complete ABS failure. Cable repair is needed, not just a sensor swap.