XJ-S

1975-1996 / Coupe / Convertible / United Kingdom

All XJ-S problems All workshop issues

Common Engine, V12

Marelli ignition issues (1989 onwards)

Symptoms

Similar symptoms to Lucas, misfiring, rough running, but less frequent and usually easier to diagnose.

Cause

The Marelli system is more reliable than Lucas but still has failure points. The distributor cap and rotor arm degrade, the coil packs can fail, and the wiring connections corrode. The system is also sensitive to moisture.

Fix

Regular maintenance, replace caps, rotors, and leads at recommended intervals.

Check coil packs.

Keep connections clean and dry.

Budget $300-600 AUD for a full ignition service.

Cost mentioned in fix

Budget $300-600

Know something we don't?

Owned a Jaguar XJ-S? Share your experience with this issue. What worked, what didn't, costs, tips. Help the community.

Submit an update

// More XJ-S problems

Other known issues

Minor Engine, V12

Cooling system failure

Engine overheats, temperature gauge climbs into the red, coolant boils over. In severe cases, head gaskets fail and coolant enters the oil.

Common Engine, V12

Head gasket weeping

Coolant appears around the head gasket line (external weep), or coolant contaminates the oil (internal failure, mayonnaise under the filler cap, white exhaust smoke).

Common Engine, V12

Lucas ignition system failure (pre-1989)

Misfiring, rough idle, hard starting, power loss, sometimes total ignition failure.

Common Engine, V12

Fuel injection faults (V12)

Rough idle, hesitation, poor fuel economy (even worse than usual), hard starting, stalling.

Common Engine, V12

Exhaust manifold cracking (V12)

Ticking or blowing noise from the engine bay, exhaust smell, sometimes visible exhaust gas.

Common Engine, Six-Cylinder (AJ6/AJ16)

Timing chain tensioner failure

Rattle from the front of the engine on cold start, which may or may not settle when warm. In severe cases, the chain jumps a tooth and the engine runs badly or stops.

View all 23 XJ-S problems