2001 MERCEDES-BENZ C32 AMG

Typical onset: 60,000-100,000 mi

Symptoms: High-pitched whine or grinding from front of engine, Rattling on cold start, Metal debris in supercharger oil, Loss of boost pressure, Check engine light with underboost codes

Fix: Supercharger removal and rebuild or replacement. Early Eaton M62 units had problematic front bearings and rubber couplers that deteriorate. Requires 8-12 hours labor for removal, rebuild/replacement, and reinstallation. Supercharger oil service every 30k miles prevents some failures but not all.

Estimated cost: $2,800-5,500

Typical onset: 70,000-120,000 mi

Symptoms: Transmission fluid leaking near radiator, Harsh shifting when hot, Transmission slipping under load, Burnt transmission fluid smell, Limp mode activation

Fix: The 722.6 5-speed is robust but depends on adequate cooling. Factory cooler lines rust through or crack at fittings. Requires replacing both supply and return lines, sometimes external trans cooler, and fluid flush. 3-5 hours labor. If caught early, trans survives; if overheated repeatedly, clutch packs burn and valve body fails requiring trans rebuild.

Estimated cost: $600-1,200

Typical onset: 80,000-150,000 mi

Symptoms: Catastrophic knocking or rattling from bottom end, Metal shavings in oil, Low oil pressure warning, Engine seizure, Milky oil or coolant loss indicating head gasket failure

Fix: M112 supercharged engines pushed hard with low-octane fuel or inadequate oil changes suffer spun rod bearings, cracked pistons, or blown head gaskets. Repair involves engine removal, complete teardown, machine work, and reassembly. 35-50 hours labor depending on extent of damage. Short block replacement or used engine swap more economical than full rebuild. Always use 91+ octane and quality synthetic oil.

Estimated cost: $8,000-15,000

Typical onset: 50,000-100,000 mi

Symptoms: Random no-start condition, Engine cranks but won't fire, Intermittent stalling at idle, Check engine light with cam/crank correlation codes, Extended cranking before start

Fix: Heat from supercharger and engine bay cooks these sensors prematurely. Crank sensor is at rear of engine behind starter (3-4 hours labor), cam sensors are easier at 1-2 hours each. Diagnosis can be tricky as failures are often intermittent until complete failure. Keep spares in the glovebox.

Estimated cost: $350-800

Typical onset: 60,000-100,000 mi

Symptoms: Excessive engine movement when accelerating or braking, Clunking when shifting into drive or reverse, Vibration at idle, Drivetrain shudder under hard acceleration

Fix: Supercharged torque destroys hydraulic engine mounts faster than naturally aspirated models. All four mounts typically need replacement as a set. Front mounts are 2-3 hours, transmission mount is 1.5-2 hours. Aftermarket polyurethane options last longer but transmit more NVH.

Estimated cost: $1,200-2,000

Typical onset: 80,000-120,000 mi

Symptoms: Hesitation or stumbling under hard acceleration, Fuel pump whine from rear of car, Limp mode under boost, No start or extended cranking, Check engine light with lean fuel codes

Fix: In-tank fuel pump wears out and inline fuel filter (often neglected) clogs restricting flow to supercharged engine. Filter should be replaced every 30k miles but rarely is. Pump replacement requires tank drop, 3-4 hours labor. Filter alone is 1 hour. Supercharged cars are less forgiving of fuel delivery issues than NA models.

Estimated cost: $800-1,400

Typical onset: 70,000-120,000 mi

Symptoms: Heat soak and power loss after spirited driving, Intercooler pump not running (audible when key is on), Check engine light with charge air temp codes, Gradual loss of top-end power

Fix: The liquid-to-air intercooler system has a dedicated electric pump that circulates coolant through the heat exchanger. Pump motor or impeller fails. Located in driver front wheel well, 2-3 hours to replace including coolant flush. Not immediately catastrophic but reduces power and increases detonation risk under sustained boost.

Estimated cost: $600-1,000