2003 ASTON MARTIN DB7

Typical onset: 40,000-80,000 mi

Symptoms: Excessive oil consumption beyond 1 quart per 1,000 miles, Cold-start smoke that persists beyond initial startup, Loss of compression on one or multiple cylinders, Rough idle that worsens when engine is hot

Fix: The supercharged AJ6 engines with Nikasil-coated bores suffer from sulfur sensitivity in pre-1996 US fuel, causing bore scoring and eventual piston/ring failure. Complete engine rebuild with steel sleeve installation or replacement short block required. 60-80 hours labor for proper rebuild including removal, machining, and reinstallation. Many shops outsource the engine work, adding time.

Estimated cost: $15,000-25,000

Typical onset: 50,000-90,000 mi

Symptoms: Transmission fluid leaking from radiator area or underneath, Transmission slipping or harsh shifts after fluid loss, Milky appearance in transmission fluid indicating coolant contamination, Overheating transmission in hot weather or under load

Fix: The ZF 5-speed automatic's external oil cooler lines and the cooler itself corrode and rupture. If coolant mixes with ATF through a failed internal radiator cooler, the transmission is typically destroyed. Requires cooler replacement, all lines, and flush if caught early. If contaminated, add transmission rebuild or replacement. Cooler job alone: 4-6 hours. With transmission work: add 20-30 hours.

Estimated cost: $1,200-2,500 for cooler/lines only, $8,000-12,000 if transmission damaged

Typical onset: 60,000-100,000 mi

Symptoms: Whining or grinding noise from front of engine that increases with RPM, Loss of boost pressure and reduced power, Rattling on deceleration from supercharger area, Check engine light with boost pressure codes

Fix: The Eaton M90 supercharger's input coupling and internal bearings wear out. Coupling failure can grenade the unit. Requires supercharger removal, rebuild with new coupler, bearings, and front seal, or replacement unit. 12-16 hours labor including removal of intake plenum and accessories.

Estimated cost: $3,500-6,000

Typical onset: Any mileage, age-related

Symptoms: Power steering fluid pooling under front of vehicle, Groaning or whining from pump at lock, Heavy steering effort especially when cold, Visible fluid weeping from high-pressure hoses

Fix: The high-pressure hydraulic lines age badly and develop leaks at crimps and connections, covered by NHTSA recall but still a widespread issue. Pump seals also fail. Multiple hose replacements often needed as one failure accelerates others. Pump: 3-4 hours. Full hose refresh: 6-8 hours due to tight routing behind supercharger.

Estimated cost: $800-1,800 depending on scope

Typical onset: 50,000-80,000 mi

Symptoms: Clunking when shifting from Park to Drive or Reverse, Excessive driveline vibration at idle in gear, Visible powertrain movement during acceleration, Rattling over bumps from transmission tunnel area

Fix: The transmission mounts deteriorate from heat and age, allowing excessive movement. Not safety-critical but accelerates wear on other driveline components. Replacement is straightforward with proper support equipment. 2-3 hours labor.

Estimated cost: $400-700

Typical onset: Any mileage, age-related

Symptoms: Intermittent misfires that move between cylinders, Random check engine lights that clear and return, Hard starting or extended cranking when hot, Erratic idle or stumbling under light throttle

Fix: The engine bay wiring insulation becomes brittle from heat cycles, causing shorts and opens in injector, coil, and sensor circuits. Diagnosis is time-consuming as failures are intermittent. Full harness replacement recommended over patchwork repairs. 16-20 hours for proper main engine harness replacement.

Estimated cost: $2,500-4,500