Miata problems/maintenance by year
General maintenance
- Keep drain rails and drain holes free from dirt blockages. Blockages cause water to pool in the rocker panels, interior, or trunk, causing serious rust damage. This is the biggest issue you will find with any Miata.
- Coolant reservoir and hoses will crack and need replacement in hot, dry climates.
- Miatas are very sensitive to alignment. If car shakes at 110 km/h+, it probably has alignment issues.
- Replacing worn-out suspension bushings, door bushings, and engine mounts are excellent "upgrades" to handling
- Prevent roof leaks: Make sure weather-stripping is properly seated. Latches may need rebuild or adjustment to seal properly.
- Many people recommend using Motorcraft Manual Transmission fluid for smoother shifting or Redline for track usage.
1990-2005
- Old radiators can wear out and leak. Note green/brown discoloration to show wear.
- Water pump will need replacement every 90k miles/150k km
- Clutch slave cylinder will often wear out over lifetime of car
- Main relay will eventually wear out and car will not start. Keep an extra in your car.
- Don't drive on empty. The fuel pump will burn out if you run on low fuel too much.
- Spark plug wires need to be replaced more often than most cars
- PCV Valve Grommet hardens and breaks. Easily fixed.
- Reverse Light Switch known to last ~80k miles (Easy fix)
- Common oil leaks:
-CAS O-ring or spot where it used to be.
-Bad aftermarket valve cover gaskets (Always check reviews).
-Rear main seal.
2005-2015
- Change idler pulley and tensioner as needed.
- Prevent leaks in windshield washer cowl so that electronics do not get damaged (Easy fix).
- These cars are astoundingly reliable and require little maintenance compared to most.
2016+
- Early versions of transmission may need to be replaced. Many motorsport enthusiasts recommend using a thicker gear oil such as Lucas 75-140 or Motul 75-140 to remedy this (Forum post).
- Convertible top can rub against the roll bar (can be modified with washers for spacing to prevent this)
- Spherical bearings on rear uprights can go bad (usually uprights are replaced entirely, but it is possible to simply repair the bearings.)
- Rust can form on the metal of the window panel.
Year-specific issues
1990
- Broken "Short nose" Crankshaft
1991
- Broken "Short Nose" Crankshaft (Early 1991 models)
1992
1993
1994
1995
Oil pressure gauge no longer accurate (1995-2005)
1996
1997
1998
1999
- Coil packs wear out quickly (common),
- Catalytic converter damaged from worn out coil packs
- EGR Issues (codes 0401 and 0402) (common)
- Idle drop when stopped. (Common)
- Crankshaft Position Sensor problems (easy fix)
- Sagging glovebox. Easily fixed.
- Clutch shudder (Rare)
- Bad thrust bearing (Typically these were fixed under warranty long ago)
- Weak springs on convertible top (Commonly already replaced)
2000
- Coil packs wear out quickly (common),
- Catalytic converter damaged from worn out coil packs
- EGR Issues (codes 0401 and 0402) (common)
- Idle drop when stopped. (Common)
- Camshaft Position Sensor problems (easy fix)
- Sagging glovebox. Easily fixed.
- Clutch shudder (Rare)
2001
- Clutch shudder caused by bad flywheel (Most fixed at this point)
- EGR Issues (codes 0401 and 0402) (common)
2002
2003
2004
2005
2006
Bad threads on fuel filler pipe
Broken coolant reservoir neck (Easy fix)
Thermostat issues (rare)
Broken throwout bearing (somewhat rare)
Starter motor failure (Relatively easy fix)
2007
Broken coolant reservoir neck (Easy fix)
2008
2009
2010
2011
2012
2013
2014
2015
2016
Roll bar may rub against soft top (fixed under warranty, DIY solutions available).
Torque spec on some PPF (power plant frame) not correct on delivery. (Easy fix)
Brake caliper rattle (Most fixed under warranty)
Transmission issues
Originally designed for the 1.5L engine, the new 6 speed transmission has serious issues with the 2.0L engine due to the added power and several weak spots in design, especially in the first versions.
V1 Transmission: Original transmission
V2 Transmission: September 5 2016
V3 Transmission: April 3rd 2017
V4 Transmission: November 1st 2017
V5 Transmission June 18 2018
2017
V2 Transmission often better than 2016 but still problematic.
2018
V3/V4 Transmission often better than 2017 but still problematic.
2019
V5 Transmission much better, but still not ideal for hard track use. See General Maintenance
2020
V5 Transmission much better, but still not ideal for hard track use. See General Maintenance
2021
V5 Transmission much better, but still not ideal for hard track use. See General Maintenance