240Z / 260Z / 280Z

1969-1978 / Coupe / Japan

All 240Z / 260Z / 280Z problems All workshop issues

Critical Electrical

Wiring Harness Deterioration

Symptoms

Intermittent electrical faults, burnt connectors, melted wire insulation. In extreme cases, electrical fires.

Cause

The original wiring insulation becomes brittle with heat and age. Connectors corrode. Previous owners have spliced into the harness for accessories, often poorly.

Fix

Inspect the entire harness, paying particular attention to the engine bay (heat exposure) and the area behind the dashboard.

Replace damaged sections.

For a car undergoing restoration, a complete reproduction wiring harness is available from companies like Wiring Specialties ($600-1,200) and is well worth the investment.

Cost mentioned in fix

$600-1,200

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// More 240Z / 260Z / 280Z problems

Other known issues

Common Electrical

Earth/Ground Issues

Dim or flickering lights, erratic gauge readings, intermittent electrical faults that come and go. The engine may misfire or run poorly.

Common Electrical

Combination Switch Failure

Turn signals, headlights, or wipers stop working intermittently or permanently.

Minor Rust

Structural Rust, Floors, Sills, Strut Towers

Perforations in the floor pans, sill (rocker panel) box sections, and front strut tower mounting points. In advanced cases, the floorboard flexes underfoot, the sills crumble when prodded, and the strut towers crack under suspension load.

Common Rust

Battery Tray Corrosion

The battery tray (right-hand side of engine bay on RHD cars) corrodes and eventually perforates. Rust spreads into the inner guard and firewall.

Common Rust

Spare Wheel Well Rust

The floor of the boot around and beneath the spare wheel well rusts through. Water pooling is visible in the boot.

Common Rust

Rear Quarter Panel Rust

Rust appears behind the rear wheels, often starting as bubbles under the paint and progressing to perforations.

View all 17 240Z / 260Z / 280Z problems