RIDEX HT Ignition Lead Set – MX-5 NA/NB Non-VVT • 685I0116

RIDEX 685I0116 HT Ignition Lead Set – MX-5 NA/NB Non-VVT

Replacement RIDEX high-tension ignition lead set for applicable Mazda MX-5 Mk1/NA and Mk2/NB petrol models using the conventional HT-lead ignition arrangement.

The HT leads carry high-voltage ignition energy from the ignition coil system to the spark plugs. Sound insulation, secure terminals and correct internal resistance are important for reliable spark delivery, smooth combustion and consistent starting.

Important fitment restriction: This set is not suitable for later 1.8 VVT/VVTi MX-5 models where the ignition-coil arrangement connects directly to two of the four spark plugs. For the 1.8-litre NB, MazSpec restricts this lead set to the earlier non-VVT application.

Common symptoms of deteriorated HT leads include intermittent misfires, rough idle, hesitation under load, difficult starting, reduced performance, increased fuel consumption or visible electrical arcing in damp or dark conditions.

• Part type: HT ignition lead / spark-plug lead set
• Material: Silicone
• Outer cable diameter: 7 mm
• Core construction: Wire wound
• Spark-plug cable connector: SAE type
• Coil / distributor connector: DIN type
• Published lead lengths: 200 mm / 380 mm and 150 mm / 275 mm
• Approximate set weight: 0.396 kg
• EAN: 4059191665679
• Quantity supplied: 1 ignition lead set
• Brand: RIDEX
• Part No.: 685I0116

Fitment advice: MazSpec confirms this set for MX-5 Mk1/NA 1.6 and 1.8 models, Mk2/NB and NB-FL 1.6 models, and the early Mk2/NB 1.8 non-VVT engine. The later 1.8 VVT/VVTi arrangement requires different ignition leads. Compare the original lead routing and relevant Mazda OE reference before installation.

Diagnostic advice: Ignition misfires can also be caused by worn spark plugs, failing ignition coils, poor electrical connections, incorrect plug gaps, fuel-system faults or compression problems. Inspect the complete ignition system before replacing parts unnecessarily.

Other items to consider: Inspect the spark plugs and ignition-coil connections at the same time. Replace spark plugs if worn, fouled or overdue for service, and check the plug wells for oil or moisture contamination.

Useful tools / consumables: Spark-plug socket where plugs are being serviced, socket and ratchet set, dielectric grease where specifically appropriate, electrical contact cleaner and suitable diagnostic equipment for checking stored misfire codes.

Difficulty guide: DIY Difficulty: Easy. Care is required to maintain the correct cylinder firing order and route the leads away from excessive heat, sharp edges and moving components.

Why RIDEX? RIDEX ignition components provide a cost-effective aftermarket servicing option. This lead set uses silicone insulation, OE-style connection types and a wire-wound core to provide dependable high-voltage transmission in the intended ignition system.

What’s in the box: One RIDEX ignition lead set. Spark plugs, ignition coils and installation tools are not included.

Installation notes: Replace one ignition lead at a time to preserve the correct firing order. Grip each terminal boot rather than pulling directly on the cable. Route each replacement lead in the original clips and guides and keep it clear of hot exhaust components, sharp edges and moving parts. Ensure every connection is fully seated at both the spark-plug and coil ends before starting the engine.