IsItAGoodCar
Reliability Guide

Common Problems with the
1992–1993 Jaguar XJS

We've identified 3 known issues that can affect the 1992–1993 Jaguar XJS. 3 of these are serious faults that could be expensive to repair.

3
Known Issues
3
Serious
0
Moderate
0
Minor

All Known Issues

Inboard Rear Brake Caliper Seizure and Fluid Overheating

SeriousBrakes

Until mid-1993, all XJS models utilized inboard rear disc brakes mounted directly to the differential housing within the rear suspension subframe. Due to their close proximity to the hot differential and exhaust pipes, the brake calipers suffer from extreme heat soak, boiling brake fluid, and hardening hydraulic piston seals. Road grime and inaccessible location mean the calipers frequently seize, while differential output shaft oil leaks saturate the brake pads, causing severe brake fade, handbrake failure, and requiring a laborious complete rear subframe drop to repair.

Est. Repair Cost: £650–£1,600
Warning Signs:

Weak handbrake that fails to hold the car on a gradient, failing the annual UK MOT test, Spongy brake pedal and smoke or burning smell emanating from beneath the rear center of the car, Severe loss of rear braking efficiency and brake fluid weeping down the differential casing

What to Inspect:
  • Inspect the inboard brake discs and calipers through the rear subframe with an inspection torch for oil contamination
  • Check service history to see if the rear axle cage has been dropped for a comprehensive brake caliper overhaul
  • Confirm the vehicle build date; late 1993 to 1996 models feature easily serviced outboard rear disc brakes
Verified by IsItAGoodCar Research TeamUpdated

Marelli V12 Twin-Rotor Ignition Distributor Melt and Catalytic Fire Risk

SeriousElectrics & Electronics

V12 models manufactured between 1989 and 1993 feature a Marelli digital electronic ignition system utilizing a single distributor with a two-tiered rotor arm firing each cylinder bank independently. If the rotor arm develops dielectric breakdown or the secondary coil fails, one entire 6-cylinder bank loses spark while the fuel injection continues spraying fuel. The raw unburnt petrol pours into the glowing hot catalytic converters, melting the ceramic substrate and creating an immediate, severe engine bay and underbody fire risk.

Est. Repair Cost: £350–£1,200
Warning Signs:

Sudden loss of engine power with the car running roughly on six cylinders instead of twelve, Overheating exhaust floorpan with glowing red catalytic converters beneath the car, Pungent smell of raw unburnt fuel followed by acrid burning exhaust heat shield smells

What to Inspect:
  • Remove the Marelli distributor cap to inspect the rotor arm for carbon arcing, burn-through, or melting
  • Verify through invoices that high-quality genuine ignition coils, silicone leads, and brass-terminal caps are fitted
  • Never continue driving if a V12 drops onto one bank; shut the engine down immediately to prevent exhaust fire
Verified by IsItAGoodCar Research TeamUpdated

Floorpan, Jacking Point, and Radius Arm Mount Corrosion

SeriousBodywork & Rust

The XJS bodyshell is susceptible to hidden corrosion, particularly on cars built before the 1994 introduction of full galvanization. Road spray and blocked scuttle drains trap moisture within the double-skinned floorpans, sills, and front chassis legs. The rear suspension radius arm forward mounting points on the floor are especially vulnerable; rust here weakens rear axle location, creating dangerous instability under heavy braking and cornering that results in immediate MOT failure.

Est. Repair Cost: £800–£2,500
Warning Signs:

Rear-end twitchiness, steering deflection, or clunking under hard acceleration or braking, Soft, yielding metal or crunching noises when lifting the car on factory jacking points, Damp carpets in footwells and visible rust holes along outer sill returns and wheel arches

What to Inspect:
  • Inspect the underside of the floorpan where the rear suspension radius arm mounts attach to the body
  • Probe front inner wings, headlights bowls, and floorpans with a wooden or plastic probe for crumbling metal
  • Lift boot carpet to inspect battery tray floor and rear fuel tank support panel for structural rust
Verified by IsItAGoodCar Research TeamUpdated

Buying Tips for 1992–1993 Jaguar XJS

  • Prioritize post-1991 facelift models (and particularly post-1993 cars); they feature outboard rear disc brakes, galvanized steel panels, and far superior rust protection.
  • On pre-1993 cars with inboard rear disc brakes, inspect the rear subframe for brake fluid leaks and caliper seizure; replacing neglected inboard pads and discs is a labor-intensive subframe-drop job.
  • On 5.3 and 6.0-litre V12 models, ensure the cooling system has been regularly flushed and fitted with fresh thermostats; V12 engines tolerate zero overheating.
  • Inspect V12 models built between 1989 and 1993 with Marelli digital ignition; ensure the distributor rotor and cap are inspected frequently to prevent single-bank misfires and catalytic converter fires.
  • Check the structural floorpans, inner sills, and rear radius arm chassis mountings; repairs to rusty structural mounting points can run into thousands of pounds.
19911994–1996
Check a 1992–1993 Jaguar XJS by Registration