RX-7 (SA/FB)

1978-1985 / Coupe / Japan

All RX-7 (SA/FB) problems All workshop issues

Common Electrical

Wiring Harness Degradation

Symptoms

Intermittent electrical failures, blown fuses, non-functional accessories, or complete electrical failure.

Cause

50+ year old wiring insulation becomes brittle, cracks, and allows shorts. Rodent damage is common on stored cars. Previous owners' modifications may have added poorly routed aftermarket wiring.

Fix

Repair individual circuits as needed, or rewire the entire car with a reproduction or custom harness. Cost: $200-500 for individual repairs, $1,000-2,500 for a complete rewire.

Cost mentioned in fix

Cost: $200-500 for individual$1,000-2,500 for a

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Other known issues

Minor Electrical

Points Ignition Wear (Early Cars)

Hard starting, misfiring, rough running, loss of power at high RPM.

Minor Engine, Rotary-Specific Issues

Apex Seal Wear and Failure

Gradual loss of compression, reduced power output, difficulty starting (especially when hot), increased oil consumption, and eventually the engine won't sustain combustion. In catastrophic failure, a broken apex seal fragment can score the rotor housing surface, requiring housing replacement.

Minor Engine, Rotary-Specific Issues

Rotor Housing Scoring

Deep scratches or grooves in the chrome or Nikasil coating of the rotor housing inner surface. Reduces compression even with new apex seals. Visible during engine disassembly.

Common Engine, Rotary-Specific Issues

Oil Metering Pump Failure

The engine receives insufficient oil for apex seal lubrication. The apex seals run dry, wear accelerates dramatically, and catastrophic engine failure follows. There may be no warning, the engine simply starts losing compression faster than normal.

Critical Engine, Rotary-Specific Issues

Coolant Seal (O-ring) Failure

Coolant leaks into the combustion chamber (white smoke from exhaust, coolant loss without external leak) or coolant leaks externally from the engine block mating surfaces. The engine overheats.

Minor Engine, Rotary-Specific Issues

Carbon Buildup

Hard carbon deposits accumulate on the rotor faces, apex seal grooves, and exhaust ports. The deposits restrict apex seal movement in their grooves, causing the seals to stick and lose their spring tension against the housing. Compression drops, power decreases, and the engine runs rough.

View all 15 RX-7 (SA/FB) problems