Home / Common Problems / Jaguar Xjs

Jaguar Xjs Problems & Known Issues

The most common Jaguar Xjs problems ranked by severity — what to watch for, what it costs to fix, and what happens if you ignore it.

Generations

XJS-Early — Early XJS
1975–1991
3.6 AJ6, 5.3 V12
XJS-Late — Late XJS
1992–1996
4.0 AJ6, 5.3 V12, 6.0 V12

Top issues to watch for

The most serious Jaguar Xjs problems ranked by severity. We track 8 known issues — here are the ones you need to know about first.

Dangerous
Structural corrosion around suspension mounting points
XJS-Early, XJS-LateAJ6, V121975–199620k–150k miles
MOT data shows the XJS fails at 12.1x the fleet average for load-bearing structure corrosion within 30cm of suspension mounting points. This affects the structural integrity around spring mountings, shock absorber towers, and subframe attachment points. The XJS monocoque construction means suspension loads are transmitted through relatively thin steel sections that are prone to corrosion from trapped moisture and road salt. Once structural integrity is compromised around suspension mountings, the car becomes unsafe to drive and requires extensive welding or replacement sections.
What happens if ignoredStructural failure around suspension mountings can cause suspension components to detach while driving, leading to complete loss of control. Repair requires cutting out corroded sections and welding in new steel, typically costing £2,000-£5,000 depending on extent. In severe cases the car may be beyond economical repair.
Independent garage
£2,000–£4,000
Specialist
£2,500–£5,000
Main dealer
£3,500–£6,500
Parts only
£200–£800
Major
Power steering system failure
XJS-Early, XJS-LateAJ6, V121975–199620k–150k miles
MOT data shows the XJS fails at 207.3x the fleet average for power steering fluid leaking or system malfunction, the highest failure rate in the entire dataset. The XJS power steering system uses a belt-driven pump feeding a rack-and-pinion system through high-pressure hoses. Common failures include pump seal deterioration, rack seal failure, and high-pressure hose rupture. The system operates at high pressure and the components are now 30+ years old with limited parts availability.
What happens if ignoredPower steering failure makes the car extremely difficult to manoeuvre, particularly dangerous given the XJS weight of 1,700kg. Complete system failure can occur suddenly through hose rupture. Pump replacement costs £800-£1,500, rack replacement £1,200-£2,500, with labour adding significantly to total cost.
Independent garage
£800–£2,000
Specialist
£1,000–£2,500
Main dealer
£1,500–£3,500
Parts only
£400–£1,200
Major
V12 Cylinder Heads
XJS-Early, XJS-LateV121975–199650k–100k miles
The V12 engine uses aluminium cylinder heads that are prone to cracking due to thermal stress from the engine's operating temperature and inadequate cooling system maintenance. The heads can crack between valve seats or around the combustion chamber, leading to coolant loss into the cylinders or external leakage. This is a well-documented issue across all V12 XJS models, with failure typically occurring when the cooling system has not been properly maintained or the engine has overheated.
What happens if ignoredCracked cylinder heads require removal and either welding repair or replacement. Head removal on the V12 is complex due to engine bay access. Repair costs typically range £2,000-£5,000 including labour. If coolant enters the oil system, internal engine damage can extend the repair significantly.
Independent garage
£2,000–£4,000
Specialist
£2,500–£5,000
Main dealer
£3,000–£6,000
Parts only
£500–£1,500
Major
Wheel bearing failure
XJS-Early, XJS-LateAJ6, V121975–19960k–150k miles
MOT data shows the XJS fails at 71.4x the fleet average for wheel bearings with excessive play. The XJS uses conventional taper roller bearings at all four corners that require periodic adjustment and greasing. The bearings are subjected to high loads due to the car's weight (1,700kg) and wide wheels, while age and lack of maintenance cause seal deterioration and grease breakdown. Failed bearings create dangerous handling characteristics and can seize completely.
What happens if ignoredWorn bearings create dangerous handling instability and can seize while driving, potentially causing wheel detachment. Bearing replacement requires specialist knowledge of preload adjustment. Individual bearing replacement costs £200-£400 per corner but multiple bearings often need attention simultaneously.
Independent garage
£200–£400
Specialist
£250–£500
Main dealer
£350–£650
Parts only
£80–£150

4 more known issues tracked

Including further major faults, wear items, electrical niggles, and generation-specific problems. Check a specific car to see which issues apply to its age and mileage.

Check a specific car →

MOT failure hotspots

Based on DVSA MOT test data. These are the items where the Jaguar Xjs fails at a significantly higher rate than the average car.

Power steering fault
Steering · 20-40k miles
MOT failure rate: 207x the fleet average
Sample: 757 tests
Emissions failure
Exhaust & Emissions · 60-80k miles
MOT failure rate: 122x the fleet average
Sample: 662 tests
Headlight fault
Lights & Electrics · 60-80k miles
MOT failure rate: 76x the fleet average
Sample: 1,374 tests
Wheel bearings worn
Suspension · 20-40k miles
MOT failure rate: 57x the fleet average
Sample: 1,147 tests
Transmission joint, belt or chain worn
Bodywork · 60-80k miles
MOT failure rate: 55x the fleet average
Sample: 473 tests
Fluid leak
Exhaust & Emissions · 0-20k miles
MOT failure rate: 46x the fleet average
Sample: 182 tests

Buying a Jaguar Xjs?

Check a specific car's service history to see if it's been looked after — franchised dealer records with dates, mileage, and work done.

Check service history

£6.99 · Full refund if no records found

Related

Jaguar Xjs reliability FAQs

What are the most common problems with the Jaguar Xjs?

The Jaguar Xjs has 8 known issues across 3 severity levels. The most serious are: Structural corrosion around suspension mounting points.

Is the Jaguar Xjs reliable?

The Jaguar Xjs has 1 dangerous and 5 major known issues. Most can be avoided with a thorough pre-purchase check and full service history.

How much does it cost to fix Jaguar Xjs problems?

Repair costs range widely. The most significant issue (Structural corrosion around suspension mounting points) costs £2,000–£4,000 at an independent garage. Minor issues can be under £200. Always get a full inspection before buying.

Which Jaguar Xjs generation is most reliable?

The XJS-Early (1975–1991) has the fewest dangerous issues (1). However, condition and service history matter more than generation — a well-maintained earlier car can be more reliable than a neglected newer one.