THINK TWICE

The NA/NB Miata's front frame rails and structural steel rust from the inside out -- 8 federal complaints (MY1999-2005) describe frame rails and front support members severely corroded, some judged to compromise the crash structure. Rust is the biggest structural risk on any 1990-2005 Miata and is worst on salt-belt cars.

Check — Inspect the front frame rails, rocker panels, floor pans, and rear subframe/differential mounts for rust, holes, and prior patch welds; a soft or perforated frame rail is a walk-away, not a negotiation.

The Miata's belt-driven crankshaft nose is a known weak point -- 7 federal complaints describe the crank pulley or timing gear shearing/coming loose on 1.6L cars (MY1990-1991) and crankshaft thrust-bearing wear letting the crank move in the block on 1.8L cars (MY1999). Either failure can ruin the engine.

Check — Listen at idle for a knock or a wobbling crank pulley; confirm the crank pulley bolt is tight and the timing marks true; watch for the pulley or crank moving fore-aft. Documented timing service by a Miata specialist is reassuring.