Buying Guide / 1998 - 2005
Mazda MX-5 NB
The second-generation MX-5 refined the original formula. Lightweight, rear-wheel drive, and pure fun, but rust is now the number one enemy on these 20+ year old cars.
The second-generation MX-5 refined the original formula. Lightweight, rear-wheel drive, and pure fun, but rust is now the number one enemy on these 20+ year old cars.
The NB MX-5 is one of the most rewarding driver's cars ever made for under £5,000. But at 20+ years old, structural rust can turn a fun weekend car into an MOT failure overnight.
We've compiled 9 known issues for the MX-5 NB in our database. Here are the five that matter most, drawn from data by MX-5 specialists and owner communities across the UK.
Go deeper: Run a free Carwise report on a specific NB to see which issues apply to that exact car, plus full MOT history, mileage checks and a personalised buyer checklist.
The MX-5 NB is now 20+ years old and structural rust is the biggest threat. Sills, rear wheel arches, the front subframe, and drain holes in the doors are the worst areas. A structurally rusted sill will fail an MOT.
Inspect sills end to end, poke with a screwdriver if necessary. Check behind plastic sill covers. Look at drain holes in the bottom of each door.
The NB uses a timing belt (not chain). If the belt snaps, the engine is an interference design and valves will hit pistons. Replacement interval is every 5 years or 60,000 miles. Many NBs have unknown belt history.
Ask for proof of timing belt replacement. If unknown, budget £300-500 for immediate replacement.
The CAS is a known failure point that causes sudden engine cutout. The car will simply die and refuse to restart until the sensor cools down. Aftermarket upgraded units are available.
Ask if the CAS has been replaced. Intermittent stalling especially when hot is the tell-tale symptom.
The fabric roof wears at the fold points and the plastic rear window becomes opaque and brittle. Aftermarket mohair tops with glass rear windows are a popular upgrade.
Inspect the roof for wear-through at fold creases. Check rear window clarity and for leaks.
Ignition coil packs can fail, causing misfires. The 1.8 VVT engine is more commonly affected. Easy and cheap to fix but can be misdiagnosed.
Listen for misfiring or rough running. Check for stored fault codes.
The NB MX-5 is the car that proved lightweight, simple, rear-drive sports cars could still work in the modern age. It does nothing in a straight line but thread it through a B-road and very little at any price is more fun.
The biggest enemy is rust, not mechanical failure. The engines are tough, the gearbox is excellent, and the chassis is pure joy. Find one with solid sills, known timing belt history, and enjoy one of the best driver's cars ever made for the price of a holiday.
Enter the registration for MOT history, mileage verification, known faults for that exact variant, and a Carwise Score.
Check a vehicle nowCompiled from independent expert sources, specialist workshops and our database of 9 known MX-5 NB issues. We are not affiliated with any source listed.
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