Question 1

What should I check for front chassis rails on a Mazda MX-5 NB?

Accepted Answer

The front chassis legs are double skinned and can rot from the inside. Specialists describe rot here as often terminal. Where to look: Under the front of the car with the undertray off: the two chassis legs running back from the front crossmember, and where they meet the floor behind the front wheels. How to test: Touch and press the chassis legs with a torch in hand. If metal flakes off or there is fresh underseal or patching, walk away or get a hoist inspection first.

Question 2

What should I check for rear sills and sill to arch joins on a Mazda MX-5 NB?

Accepted Answer

Rust in the rear sills and where they join the rear arches is widely reported, and many cars already have patch repairs. Where to look: The rear end of each sill and the join with the rear wheel arch, inside and out. How to test: Use a magnet and probe gently to judge any repair. A patch welded over rusty metal keeps rusting underneath.

Question 3

What should I check for rear wheel arches on a Mazda MX-5 NB?

Accepted Answer

Rear arches rust from the inside out, so visible bubbling is usually only part of it. Blocked drains make it worse. Where to look: Inside the lip of each rear wheel arch. How to test: Run a finger inside the arch lip and look with a torch for flaking metal or filler.

Question 4

What should I check for hood drains and roof leaks on a Mazda MX-5 NB?

Accepted Answer

Leaking roofs and blocked drain holes are commonly reported. The fabric also tends to tear at the fold above the side windows. Where to look: The drain holes behind the seats, the carpets under the seats, and the hood fabric above each side window. How to test: Lift the carpet and feel for damp. Raise and lower the hood by hand during the viewing and check it closes tight. The front latches should not open without pressing the safety button.

Question 5

What should I check for rear main seal and sump gasket on a Mazda MX-5 NB?

Accepted Answer

Oil leaks at the gearbox bellhousing are reported, and in most cases come from the rear crankshaft seal or the sump gasket. Where to look: The join between the engine and gearbox, and the sump edge, from underneath. How to test: Look for wet oil and caked dirt where the engine meets the gearbox and around the sump.

Question 6

What should I check for radiator and cooling system on a Mazda MX-5 NB?

Accepted Answer

Cooling system neglect and radiator wear are commonly reported. A radiator whose plastic has faded from black to light grey is near the end. Where to look: The plastic end tanks of the radiator and the coolant expansion tank. How to test: With the engine cold, look at the radiator plastic colour and for crust at the seams. Check under the oil filler cap for mayonnaise.

Question 7

What should I check for suspension bushes and rear calipers on a Mazda MX-5 NB?

Accepted Answer

Tired bushes, worn dampers and seized brake calipers are listed as common problems. Where to look: The wishbone bushes at each corner and the rear calipers. How to test: Look for cracked bushes. On the test drive listen for knocks and check the car brakes in a straight line.

Question 8

What should I ask the seller of a Mazda MX-5 NB?

Accepted Answer

Has the car been on a hoist recently, and has anyone looked at the front chassis legs? Has any rust repair been done on the sills or arches, and are there photos from before the underseal? When were the cambelt and water pump last done, and at what km? Is it a 5 speed or 6 speed, and does it have the LSD? Has the hood been replaced, and has the carpet ever been wet?

Mazda MX-5 NB (1998 to 2005): buying guide, problems and NZ numbers

Key facts

On NZ roads

Known weak points

Front chassis rails

Rear sills and sill to arch joins

Rear wheel arches

Hood drains and roof leaks

Rear main seal and sump gasket

Radiator and cooling system

Suspension bushes and rear calipers

Service items

Questions to ask the seller

New Zealand notes

US recalls