Aston Martin · 2004-2016
DB9
Known issues.
The DB9 is a mature, useable V12 GT, but most examples are now old enough for age-related faults to matter as much as mileage. Cooling, ignition, and water ingress are the headline areas to watch.
What to watch forLiving with the DB9
Ownership snapshot
The healthiest DB9s are used frequently enough to keep seals, batteries, and fluids alive, but not run on a shoestring. A thick history file is worth more than cosmetic perfection.
What to watch for
4 issues01Cooling system ageing and thermostat complaints
Temperature creeping in traffic, weak cabin heat, or coolant level changes without an obvious external leak.
All DB9 years, especially older cars on original hoses, expansion components, or thermostats.
Cooling system ageing and thermostat complaints
Temperature creeping in traffic, weak cabin heat, or coolant level changes without an obvious external leak.
All DB9 years, especially older cars on original hoses, expansion components, or thermostats.
- Driveability
- Stop driving if the temperature climbs unexpectedly or coolant loss is obvious.
- DIY or specialist
- Inspection only for owners. Repair work is specialist territory.
Early warning signs
- The temperature gauge moves more in traffic than it used to
- Coolant smell after a hot run
- Evidence of dried coolant staining around hoses or joints
Likely root causes
- Ageing hoses and seals
- Thermostat sticking or slow to react
- Cooling system components nearing the end of their service life
Typical cost context
- A hose or thermostat job can be moderate if caught early.
- An overheating event with follow-on diagnosis is far more expensive and should be avoided.
Prevention
- Inspect the cooling system annually, not only when the gauge moves.
- Keep old coolant service records in mind instead of assuming low mileage means low risk.
- Treat any coolant smell seriously.
02Coil, plug, and vacuum-related rough running
Slight misfire, uneven idle, sluggish part-throttle response, or emissions-related warning lights.
Across the range, especially ageing cars or cars used mostly for short trips.
Coil, plug, and vacuum-related rough running
Slight misfire, uneven idle, sluggish part-throttle response, or emissions-related warning lights.
Across the range, especially ageing cars or cars used mostly for short trips.
- Driveability
- Gentle driving may be possible, but do not ignore persistent misfire or emissions warnings.
- DIY or specialist
- Basic checks are realistic; diagnosis and deeper access are usually better with a specialist.
Early warning signs
- Hot idle becomes slightly lumpy
- The car feels less smooth under gentle acceleration
- Stored mixture or misfire codes appear before the warning becomes permanent
Likely root causes
- Ageing ignition components
- Vacuum hose leaks or brittle rubber lines
- General tune-up items left beyond sensible age
Typical cost context
- A straightforward ignition refresh is usually a medium-cost job.
- Long diagnostic time rises if multiple small age-related faults overlap.
Prevention
- Refresh ignition service items on age as well as mileage.
- Inspect brittle hoses during routine maintenance.
- Do not keep clearing a warning without identifying the cause.
03Water ingress around door and boot seals
Musty cabin smell, damp carpets, condensation, or electronic oddities after heavy rain.
Older coupes and Volantes, especially cars stored outside or infrequently checked.
Water ingress around door and boot seals
Musty cabin smell, damp carpets, condensation, or electronic oddities after heavy rain.
Older coupes and Volantes, especially cars stored outside or infrequently checked.
- Driveability
- Usually driveable, but damp electrical areas can create wider faults if ignored.
- DIY or specialist
- Inspection and drain cleaning are owner-safe. Persistent leaks usually need specialist attention.
Early warning signs
- Light fogging inside the car after rain
- Boot trim feels slightly damp
- Drain holes show signs of blockage
Likely root causes
- Aged or poorly seated seals
- Blocked drains
- Previous body or glass work not finished properly
Typical cost context
- Cleaning drains and reseating trim is relatively minor.
- Interior drying and electrical fault tracing raise costs quickly if left too long.
Prevention
- Keep drains clear and seals clean.
- Investigate cabin condensation early.
- Do not store wet carpets inside the car.
04Touchtronic shift quality decline from overdue service or adaptation drift
Lazy or abrupt shifts, hesitation when selecting drive, or a gearbox that feels less smooth than it should.
Touchtronic cars, especially those with patchy fluid history.
Touchtronic shift quality decline from overdue service or adaptation drift
Lazy or abrupt shifts, hesitation when selecting drive, or a gearbox that feels less smooth than it should.
Touchtronic cars, especially those with patchy fluid history.
- Driveability
- Usually driveable if shifts are merely poor, but avoid repeated harsh manoeuvres and investigate early.
- DIY or specialist
- Garage-only for meaningful diagnosis and service.
Early warning signs
- Cold shifts feel reluctant
- The gearbox seems to pause longer than normal when manoeuvring
- Previous owners describe the behaviour as 'normal' without service evidence
Likely root causes
- Aged fluid or missed service interval
- Adaptation values drifting over time
- Underlying electrical or low-voltage issues
Typical cost context
- A fluid service and recalibration is far cheaper than waiting for a major gearbox complaint.
- Hard faults or repeated adaptation failures raise the bill sharply.
Prevention
- Maintain fluid service history even if mileage is low.
- Keep battery voltage strong.
- Do not normalise poor shift quality on a test drive.
No matching issues
Try a different symptom or severity.
Severity reflects potential impact, not fault frequency. Diagnosis and regional labour rates affect the final repair cost.
Frequently asked questions
What is the smartest first inspection on a DB9?
Cooling system condition, battery health, and evidence of regular service work. Those three quickly tell you whether the car has been looked after properly.
Are DB9 issues usually age-related or mileage-related?
Age-related faults are often the bigger story now, especially on low-mileage cars that have spent long periods stored.