IsItAGoodCar
Reliability Guide

Common Problems with the
2002 Jaguar XK8 / XKR (X100)

Comprehensive mid-cycle revision brings bored-out 4.2-litre AJ34 engines, modern 6-speed ZF automatics, and standard factory metal timing chain tensioners.

What changed for 2002

  • •Displacement increased to 4.2 litres producing 300 bhp (XK8) and 400 bhp (supercharged XKR)
  • •ZF 6HP26 6-speed automatic transmission replacing earlier 5-speed ZF and Mercedes units
  • •Factory adoption of durable metal-bodied timing chain tensioners and morse-type chains
  • •Subtle styling refresh including revised front bumper grille, clear headlamp lenses, and updated badging

Common MOT watch-outs

  • !Perished rear suspension A-frame bushes and corroded rear subframe mounting brackets
  • !Hairline cracks in coil springs and leaking adaptive CATS damper electrical wiring looms
  • !Corrosion around rear quarter panels, inner arches, and front subframe mounting points
  • !Exhaust emissions failure caused by aged lambda sensors and deteriorating catalytic converters
2
Known Issues
2
Serious
0
Moderate
0
Minor

All Known Issues

Plastic Secondary Timing Chain Tensioner Failure

SeriousEngine

Early 4.0-litre AJ26 and AJ27 V8 engines utilized first- and second-generation plastic-bodied secondary timing chain tensioners. Over repeated heat cycles and exposure to acidic engine oil, the plastic body develops stress fractures and the plastic shoe breaks off. This allows the secondary timing chain to slacken and skip teeth on the camshaft sprockets, causing piston-to-valve collision that results in bent valves and catastrophic engine destruction.

Est. Repair Cost: £800–£1,500
Warning Signs:

Loud metallic rattle or clattering noise from the front timing cover on cold startup, Rough erratic idling with misfire codes P0300 to P0308 stored in the engine ECU, Sudden loss of compression and failure to restart after a cold start attempt

What to Inspect:
  • Inspect service history for documented invoice proof of metal-bodied Gen 3 tensioner retrofits
  • Remove the right-hand (bank 1) camshaft cover to visually inspect tensioner body composition
  • Listen attentively with a mechanic stethoscope to the upper timing covers during cold startup
Verified by IsItAGoodCar Research TeamUpdated

Rear Suspension Subframe and Chassis Sill Corrosion

SeriousBodywork & Rust

The X100 chassis traps road mud, wet salt spray, and moisture behind the full-length plastic sill covers, inside the rear wheel arches, and across the fabricated rear subframe mounting points. Structural steel inner sills and front footwell floor outriggers corrode from the inside out. By the time bubbling paint appears externally, extensive structural welding is required to meet UK MOT requirements.

Est. Repair Cost: £600–£2,000
Warning Signs:

Crunching or creaking sound when placing a workshop trolley jack beneath factory jacking points, Bubbling paint along lower front wheel arch edges and forward of the rear wheels, UK MOT failure advisory for structural corrosion within 30cm of safety mounting points

What to Inspect:
  • Use a high-intensity inspection torch to probe inner sills and seat belt anchorage floor sections
  • Inspect the rear suspension A-frame mounting plates and crossmember bushes for flaky rust
  • Examine past UK MOT history for repeat advisories regarding underbody and floor corrosion
Verified by IsItAGoodCar Research TeamUpdated

Buying Tips for 2002 Jaguar XK8 / XKR (X100)

  • Test the ZF 6-speed automatic transmission for the infamous 2-1 shift lurch and check mechatronic plug seals for weeping fluid
  • Check Brembo brake calipers (standard on XKR 100/optional) for seized cross-over pipes and uneven pad wear
  • Verify that air-conditioning blows ice cold; evaporator and condenser pinhole leaks are expensive dashboard-out repairs
  • Examine the 4.2-litre cooling valley pipes under the supercharger/intake manifold for baked rubber leaks
20012003–2006
Check a 2002 Jaguar XK8 / XKR (X100) by Registration