1996 ASTON MARTIN DB7

Typical onset: 40,000-80,000 mi

Symptoms: Sudden loss of compression in one or more cylinders, Metallic rattling or knocking from lower end, Excessive oil consumption (more than 1 qt per 500 mi), White smoke on startup that doesn't clear, Scored cylinder walls visible on borescope

Fix: The Nikasil cylinder linings react badly to high-sulfur fuel (common in mid-90s USA). Bores score, rings fail, then rod bearings go. Complete engine rebuild or replacement required: 40-60 hours labor for removal, machine work, reassembly. Many owners opt for factory short-block exchange or used engine swap. This is why you see so many pistons/rings/bearings jobs listed.

Estimated cost: $15,000-25,000

Typical onset: 60,000-90,000 mi

Symptoms: Whining or grinding noise from front of engine that increases with RPM, Loss of boost pressure and power, Supercharger oil leaking from nose drive, Rubber coupler debris in intake tract

Fix: The rubber coupler between crank pulley and supercharger disintegrates, and the needle bearings in the snout go out. Supercharger must come off (8-12 hours), rebuild kit installed, and proper shimming performed. Often discover additional boost control valve issues while in there.

Estimated cost: $2,800-4,200

Typical onset: 50,000-100,000 mi

Symptoms: Transmission fluid leaking from cooler lines or radiator, Harsh shifts or slipping when hot, Milky pink fluid (coolant contamination), Clunking on acceleration/deceleration from worn mounts

Fix: The ZF 4HP22 transmission runs hot under the supercharged engine. Cooler lines corrode and leak, external cooler clogs, and rubber mounts collapse. Cooler line replacement 3-4 hours, mounts 2-3 hours. If coolant mixes with ATF, flush and pray the transmission survives.

Estimated cost: $800-1,500

Typical onset: 70,000-120,000 mi

Symptoms: Overheating with no external leaks, White exhaust smoke, Pressurized cooling system when cold, Oil in coolant or vice versa, Misfires after sitting overnight

Fix: Supercharger heat stress and marginal cooling system cause gasket failures, often both banks simultaneously. Heads must come off (20-28 hours), check for warpage, resurface, replace all gaskets and timing components while accessible. Common to find corroded liners underneath.

Estimated cost: $6,500-9,500

Typical onset: any mileage

Symptoms: Hard starting when hot, Stumbling or cutting out under boost, Fuel smell in cabin or trunk area, Check engine light with lean codes, Long crank time

Fix: Fuel filter clogs quickly (hidden in bizarre location under car, 2 hours to replace properly), in-tank pump fails, and pressure regulator in engine bay leaks. The supercharged engine is very sensitive to fuel pressure variations. Replace filter every 15k mi regardless of manual interval.

Estimated cost: $400-1,200

Symptoms: Intermittent gauge failures, Central locking operating randomly, Windows or mirrors not working, Battery drain when parked, Corrosion in footwell fuse boxes

Fix: Classic Jaguar wiring quality. Water ingress through windshield seal or A/C drain causes corrosion in body control module and footwell connectors. Diagnosis is time-consuming (4-8 hours), repairs involve cleaning grounds, repairing harness sections, sometimes BCM replacement (NLA from factory, used only).

Estimated cost: $600-2,500

Typical onset: 60,000+ mi

Symptoms: Overheating in traffic or under load, Coolant leaks from multiple locations, Plastic thermostat housing cracking, Brittle hoses that burst without warning

Fix: The supercharged engine runs very hot, and all plastic cooling components age poorly. Budget for complete cooling system refresh: radiator, all hoses, thermostat housing, water pump, expansion tank. Do it all at once (12-16 hours) or chase leaks forever. Non-negotiable preventive maintenance.

Estimated cost: $2,500-4,000