9 Common Mazda MX-5 Miata Problems (Explained)

The Mazda MX-5 Miata, which debuted in 1989, has gone on to become the bestselling two-seat roadster of all time. 

Even after 30 years, it remains a popular choice among enthusiasts for its affordability, reliability, fun factor and charm. 

In this article, we’ll take a look at some of the common problems and issues Miata owners have had across the last four generations. 

1. Severe Rust Problems 

First and second generation Mazda Miatas from 1989 up to the 2005 model year have lots of known rust problems.

In a lot of cases, different sections of the body start rusting from the inside. When you start seeing rust on the exterior body panels, it’s usually much worse underneath and lots of structural pieces have already been completely eaten up. 

Common Miata rust areas include:

• Rocker panel
• Fenders
• Wheel arches
• Front frame rail
• Floor boards
• Trunk
• Rear deck
• A-pillars

Aside from being unsightly and possibly unsafe, a rusted Miata is going to be much harder to work on since many of the bolts will be completely rusted out and stuck in place. 

Here’s how two owners on the Miata.net forum described the issue:

‘I have a 2004 NB MSM which is starting to show rust bubbles on the passenger side behind the door, but above the rocker panel; also on the trunk lid at the corners of the spoiler.’ 

‘A guy at the upper part of my neighborhood has a ’99 and it’s starting to rust at the rear rocker panel on the drivers side just like an NA.’ 

Older Miatas with a history of road salt exposure are prone to rust issues. They become rusty when road debris and moisture get stuck inside the underside and in between the seams of the sheet metal. The convertible top’s drain holes can also become blocked, causing water to accumulate and saturate various areas of the car’s body. 

To keep an older Miata rust-free, avoid driving it during the winter and keep it garaged to protect it from the elements. You should also regularly check the drain holes to make sure they are not blocked. To check for rust on the floor boards, you’ll have to peel off the carpet to get a better look. 

2. Coolant Leaks

The Miata’s cooling system uses many plastic parts that eventually degrade and crack over time, causing coolant leaks and overheating issues.

Coolant leaks are quite common in NA and NB Miatas. It’s also becoming a more common problem in the third generation NC Miata, especially since some examples are over 15 years old.

Usual sources of coolant leaks in a Miata include:

• Radiator
• Coolant expansion tank
• Coolant hoses and pipes
• Water pump
• Thermostat housing

The first things that break are usually the radiator and the coolant expansion tank. When the top of the radiator turns brown, when it used to be glossy black plastic, it’s usually time to replace it to avoid engine cooling problems in the very near future.

Here’s how one Miata owner described their issue:

“I have a 1993 1.8 which left a nice puddle on the floor today. I jacked it up and seems to be coolant running down behind the crank pulley and dripping off the front of the sump – that’s all I could see on Jack stands.“

Replacing cooling system parts is considered normal maintenance as a car gets older.

A new replacement radiator usually costs around $200. Many owners also replace the stock parts with aluminum radiators and tanks which are more durable.

If you let the car run without coolant and let it overheat, you could damage the head gasket and even the cylinder head which will be significantly more expensive to fix.  

3. Infotainment Screen Delaminating

Lots of fourth generation (ND) Miata owners have had issues with the infotainment screen delaminating.

Owners usually start noticing tiny white cracks that look like crystallization. It’s also commonly referred to as spider webbing. 

It happens more often if the car is parked outside in the hot sun which causes the adhesive in the screen to break down.

These screen issues typically affect the 2016 to 2017 model years of the ND Miata which had a silver bezel around the screen. However, it seems that even the newer screens used in the later models, which have a black bezel around it, can also suffer from delamination problems. 

Here is how a few owners described their dilemma:

“I have a 2017 mx5. My infotainment display has cracks inside. Since my warranty is up, Mazda said they would do a good gesture replacement for 200$. I asked what the cost of the display was and they said close to 1200$.”

Mazda released a TSB (Technical Service Bulletin) to address the screen delamination issues in several models and recommends replacing the digitizer. Unfortunately, the screen will only be replaced if the car is still under warranty. 

If you want to go the DIY route, you can find the digitizer and the actual screen itself online. Just make sure you get a high quality unit because some replacement screens do not have the same image quality as the original.

Some owners have also successfully swapped in screens from other Mazda models like the Mazda3, Mazda CX3, and even the Toyota Yaris, which is essentially a rebadged Mazda2.

Related: 11 Best & Worst Mazda MX-5 Miata Years (Explained)

4. Cracked A/C Line

Several fourth generation (ND) Miata owners have had problems with their air conditioning system completely stopped working after the first year or two of ownership.

This is often caused by a cracked A/C line which eventually lets all the refrigerant out of the system. The A/C lines typically crack due to the engine’s vibrations.

Here is how two Miata owners described their experience:

“I have 16k miles on my 2019 club was hearing a hissing noise from passenger footwell. Next day, I had no a/c at all. Apparently, upon bringing it to dealer, a cracked a/c line was the issue.”

“I just got this fixed yesterday after my AC stopped working. Cooler pipe was cracked and leaking at just under 25k miles on my ’19. Replaced and recharged AC under warranty.”

Mazda addressed this problem in a TSB which recommends replacing the A/C line with a new part that has been reinforced. 

According to the TSB, this problem only should affect the 2016 to 2018 models, but it also seems to happen in the 2019 models.

If your car is still under warranty, take it back to the dealer to get the A/C checked and fixed. Your local mechanic should also be able to handle the repair if you’re trying to save on repair costs. The part is only around $90, but you’ll also have to pay to get the system recharged with new refrigerant. 

5. Transmission Problems 

Early model years of the fourth generation (ND) Miata had several cases of early manual transmission failures.

Symptoms of transmission problems include:

• Grinding noises when shifting
• Can’t shift into 2nd or 3rd gear
• ‘Notchy’ gear shifts
• Metal bits in transmission fluid

Transmission failures typically only affect the 2016 to 2017 model years of the soft-top version. 

When the transmission went, it would usually happen within the first 10,000 to 20,000 miles. In some cases, some owners had to have their transmission replaced twice. 

Early first generation Miatas also had issues where the transmission would get stuck in fifth gear or reverse. But aside from these reported problems, Miata transmissions are usually quite reliable.

Here’s how one 2016 Miata owner described their experience:

“While driving on a public 2-lane road and upshifting into 3rd gear at about 6,500 rpm my transmission failed. I determined that I could still drive in 1st gear and, driving only on the shoulder, drove the car to a wider, safer spot.”

According to a TSB released by Mazda, transmission problems should only affect cars built before September 2016. They eventually updated the transmission components to make them less prone to failure. Newer ND Miatas should be using the fifth version of the manual transmission which has had many improvements.

Transmission failures don’t affect all early ND Miatas. Cars with higher mileages are less likely to have future transmission problems as long as you keep up with its maintenance. However, aggressive driving, regularly tracking the car, and using forced induction might increase the chances of failure.

6. Hard Top Issues 

The third generation (NC) Miata was the first model to be equipped with the Power Retractable Hard Top (PRHT). 

These were more complicated than the manually operated soft top, and over time, owners would run into problems where it wouldn’t operate properly.

The most common problem is that the top indicator would continuously blink which indicates that the retractable hard top is encountering an issue of some sort.

Here’s how two owners described their problems:

“I bought myself a 2010 NC PHRT about two months ago, runs great. Last weekend though, the top indicator light stays on continuously and beeping will not stop, whether the top is up or down.”

“I bought my ’07 PRHT MX5 a month ago. I would get a random flashing light. If parked outside in the sun for a few hours it would not go down most the time.”

The blinking light for the top is usually caused by faulty limit switches which detects whether the top is fully retracted or closed. The switches are cheap to replace but you may have to tear apart the rear deck to get to them. 

In some cases, simply bending the metal bits that make contact with the limit switches also fixes the problem. A faulty hard top button will also make the hard top inoperable, but this is also very easy to fix.

If your power windows are not working, you also won’t be able to use the power hard top. To fix this, you’ll usually need to replace the window switch module.

7. Soft Top Issues

The soft top on all older Miatas will eventually become extremely worn out and torn.

Aside from degradation caused by the elements, the top will get worn out, cracked, and torn after repeatedly going up and down for several years. This leads to leaks whenever you’re driving in the rain which isn’t any fun at all.

After 10 to 15 years, it can also become faded after being out in the sun for such a long time.

Older NA and NB Miatas were originally equipped with vinyl hard tops. In the later years, Mazda also offered canvas or cloth tops.

The rain rails in the back will also eventually crack and cause water to pool in the rear deck and trunk area which often causes major rust issues.  

Aftermarket replacement soft tops typically cost around $600 to $1,000 depending on the model year of your Miata. You can go the DIY route for the installation, but most people pay their local mechanic or car upholstery shop a few hundred dollars for a professional install.

8. Engine Failures

Although Miata engines are known for their overall reliability, early years of the third generation (NC) Miata had several reports of early engine failures.

When it was first released in 2006, there were reports of engine failures happening at 10,000 to 20,000 miles were caused by seized rod bearings and rod failures.

Over the years, more and more 2006 to 2008 Miatas, also known as the NC1 model, have been suffering from engine failures at higher mileages. If your car didn’t suffer from an engine failure early on, it could still be affected later on in its life, especially if it isn’t regularly maintained.

Here’s how two owners on the Miata.net forum described their experience:

“Mine went at 115k. I had only owned the car for 2 days and a rod went through the crankcase.”

“I bought mine with 119,000 miles on it…3 days after purchase, I had a spun rod bearing.”

When the third generation Miata was facelifted and updated for the 2009 model year, also known as the NC2, Mazda also updated many engine components to improve its reliability.

Regular oil changes using the right type of oil should help you avoid future engine problems if you’re driving an early model third gen Miata. If you drive aggressively or regularly take your car to the track, you should change your oil more frequently.

Many Miata enthusiasts suspect that the NC Miata’s engine failures are caused by oil starvation problems, so keeping the engine in great condition and replacing faulty parts as soon as possible should help prolong its life.

If you hear a knocking noise or notice that the oil pressure is reading low, it’s best to stop driving and have the car towed to a mechanic who can further diagnose the problem.

Related: How Long Do Mazda MX-5 Miata Last? (12 Important Facts)

9. Timing Belt Failures

NA and NB Miatas were equipped with timing belts instead of timing chains.

Timing belts need to be replaced every 60,000 miles. When the timing belt snaps, the engine will simply stop running. 

With the release of the third gen NC Miata, the engines started using timing chains which have longer service intervals.

Fortunately, the first and second generation Miatas had non-interference engines so you don’t have to worry about catastrophic engine damage when the timing belt suddenly breaks.

Replacing the timing belt in an older Miata is relatively cheap and easy, so there’s no reason to put it off for longer. If you bought your Miata used without any service records, it’s best to replace the timing belt as a precaution in case the current one installed is already several years old and worn out.

Mazda MX-5 Miata Pros & Cons

Pros

• Excellent handling
• Affordable
• Convertible top
• Easy to maintain
• Great reliability
• Fuel efficient

Cons

• Limited trunk space
• Lack of headroom
• Loud wind noise at highway speeds

What Do The Reviews Say?

“The Miata is a light, nimble, precise and easy-to-drive sports car even when you’re pushing its limits. At our test track, our manual-equipped Miata accelerated from 0 to 60 mph in 6.4 seconds. That’s respectable but a bit off the pace of the Subaru BRZ (6.1 seconds) or a hot hatch such as the VW Golf GTI. Braking performance is solid, and we measured a stop from 60 mph in just 113 feet.”

“Small two-seat roadsters aren’t known for comfort, but the Miata is surprisingly livable in the day-to-day grind. You’ll notice big lumps and bumps in the road as the Miata tends to crash over pavement that’s in poor shape, but smaller imperfections are much more muted.” 

“One unfortunate reality of the Miata — you’ll be shocked to read this, we know! — is its exceptional amount of wind noise. The cabin can be a truly uncomfortable place to be with the top up on the highway. Shouting is occasionally required to speak with passengers.” 

“Engaging driving dynamics and open-top fun sound enticing, but the Miata isn’t for everyone. Its very small interior will force tall people to shoehorn themselves in — or not fit at all. The trunk is so small a weekend trip for two might be out of the question unless you pack very lightly. The Mazda also doesn’t offer as much tech or as many advanced driver aids as some of its rivals do.”

“Despite being small, the Miata isn’t flimsy. It’s built well and everything has a solid feel to it, though the gear lever in our test vehicle constantly rattled around inside the gate. Typical of Mazdas these days, an abundance of soft plastics and faux leather coverings give the interior an upscale feel. While the price can creep in upper trims and with option packages, the Miata is a good value overall.”

2023 Mazda MX-5 Miata | Edmunds

What’s the Resale Value of a Mazda MX-5 Miata?

Here’s a quick look at used car pricing on Edmunds at the time of writing.