The RX8 Reliability – Are They a Good Investment?

Mazda has a long history of being the company that tests the limits and pushes the envelope. The Mazda RX8, on the other hand, was one of the most intriguing debuts ever, and it has only grown more exciting since its 2003 debut.

Even if you exclude the cutting-edge components like the Wankel rotary engine and coupe-like body of the RX8, true rear-wheel drive, manual gearbox, and naturally aspirated sports vehicles are uncommon on the market today. Let’s discuss the RX8 reliability of Mazda.

The Nissan 350Z and Honda S2000 were some of the vehicles the RX8 had to compete against when it first came out, and we also contrasted it with some mechanically advanced vehicles like the Volkswagen Golf R32 and Subaru Impreza WRX.

The Mazda RX8 is currently an affordable discovery, and while purchasing used cars has risks compared to many of its competitors, there are also benefits. The RX8 will provide you with fun and distinctive driving experiences if the gasoline costs are manageable. Few automobiles in existence today have the mental impact of a Mazda RX8.

Without even mentioning how the car maneuvers around curves, the sound the rotary engine makes when it approaches 9,000 rpm sends a chill down your spine. But there is a cost associated with these feelings. Undoubtedly one of the least dependable cars money can buy is the RX8. What factors influence the Mazda RX8 reliability?

The Design of the RX8 By Mazda

The Mazda RX’s distinctive rotary engine lies at the heart of its design. With redesigned exhaust ports that were located on the side of the rotor housings rather than its periphery and new rotor seals, which the rotary design had long suffered with, this engine, known as the Renesis, was a significantly improved version of the 2-rotor 13B fitted in the RX-7.

In contrast to the RX-7, the Renesis was naturally aspirated rather than turbocharged, but it was still capable of producing 237 horsepower at 8500 rpm. There was also a 189bhp version available. While the former had a 6-speed manual transmission, the latter had a 5-speed with different ratios.

1. Mazda RX 8 SPIRIT R
Mazda RX-8 SPIRIT R by Tokumeigakarinoaoshima / CC0. Many Mazda RX8 owners claim that the vehicle has a terrible propensity for overheating. If you drive for a while, you might see some smoke or steam coming from the car’s undercarriage.

Because the gearbox was developed using prototypes from the third-generation Mazda MX-5, the underpinnings were very similar to those of that vehicle.

With a multi-link rear suspension and a double-wishbone front suspension, Mazda managed to keep the weight at a manageable 1300 kg. In contrast, the 1.8-liter Mazda 6 weighed 1345 kg and was less potent and conventional.

Did They Do Anything Else?

The RX8’s interior wasn’t as impressive as some of the other German options, but its distinctive dashboard and low seating position gave it a peculiar air. It was also quite practical.

Several special editions of the problematic model were made available during its run of manufacturing, but the PZ is by far the most intriguing. The majority of the modifications were made by Prodrive to enhance the car’s handling.

The result was a more serious sports variant with the same amount of power but with Bilstein dampers, OZ-racing wheels, and a louder exhaust.

In 2008, more substantial modifications were made, including a facelift to reflect the brand’s corporate theme of the time, altered geometry, a high specification, chassis stiffness, and a short final drive.

Due to mounting concerns over the emissions regulations and the RX8’s dismal sales, Mazda stated that they would stop producing the vehicle in 2011.

What Engine Powers the RX8 By Mazda?

A 1.3L Renesis two-rotor rotary engine powers our protagonist for today. This engine produces 159 lb.-ft of torque at 5,500 rpm and 212 HP at 7,500 rpm.

When combined with a manual transmission, the Mazda RX8 rotary engine can reach 232 HP at 8,500 rpm. Customers were constantly captivated by Mazda’s RX-series rotary engine despite all the warning signs. There’s a rationale behind that.

When compared to a traditional piston engine, this engine has many benefits. For instance, they provide great power with little displacement, fewer moving parts, and a lighter frame (the RX8’s engine has only 1.3 liters yet produces 232 HP). The engineers were able to improve engine placement because of the engine’s tiny size and lightweight.

Furthermore, the RX8 has smoothly mastered the skill of balancing ride comfort with handling precision, a skill that is difficult for many vehicles to achieve when it comes to dynamics. The rotary engine’s output is pretty astounding, but it uses a lot of fuel, which is a problem. Not to mention that the torque barely reaches its maximum in the upper range.

Which are the Common Mazda RX8 Reliability Issues?

What makes the Mazda RX8 a vehicle to avoid? When deciding whether to purchase this, consider the following:

2. 2004 Mazda RX 8
2004 Mazda RX-8 by OSX II / CC BY 2.0. The RX8 has a weak spot underneath its hood. The 1.3-liter Renesis rotary engine has a bad reputation for being a gas guzzler and the worst part is that it impacts the entire engine. Rotors, which are used in this engine in place of pistons, deteriorate over time.

Engine Issues

1. Reduced Thermal Efficiency

Under the hood of the RX8, there is an Achilles’ heel. The Renesis 1.3-liter rotary engine is notorious for being a poorly constructed, gas-guzzler, and the worst part is that it affects the entire engine. This engine uses rotors in place of pistons, and with time, they degrade.

In other words, the engine revs too quickly, which causes the apex seals on the corners of the rotors and their interaction with the rotor housing to deteriorate more quickly. If these seals become worn out, you must replace them, which necessitates an engine rebuild. However, there are steps you can take to lengthen your life.

Wankel engines have lower thermal efficiency by the nature of their construction. The poorly built combustion chamber can be partially attributed to the low compression ratios.

2. Complexity In Maintaining the Engine Sealed

Gas in the chambers inside the engine is not permitted to cross-contaminate or enter the wrong chamber. Although the apex seal is designed to keep the gas in the appropriate chamber, it occasionally fails.

Even though combustion always occurs on one side, problems can still arise if there is a significant temperature difference. The seal won’t keep the gases in place as the metal swells.

3. Reduced Fuel Efficiency

To make sure your automobile has enough gas, you’ll almost always need to check the fuel levels.

4. Dreadful Emissions

The rotary engine’s biggest problem is unquestionably this. With this engine, you burn through a lot of gasoline, and it might also be difficult to secure various gas chambers. Additionally, the thermal efficiency is poor.

5. Issues with Overheating

The Mazda RX8 has a reputation for having horrible overheating tendencies, according to many of its owners. You might see some smoke or steam coming from the car’s undercarriage if you drive for an extended period.

Additionally, there’s a risk that the needle on the engine temperature gauge may be smoking.

Leaks and the potential for the fan connection system to explode will occur from the car’s coolant not being supplied consistently.

6. Brake Problems

The Mazda RX8 had an outstanding braking system when it first rolled off the assembly line. Owners began to notice, though, that the car was slightly noisier after a while than in the beginning.

It eventually became too loud for people to continue driving. The brakes would make creaking noises and dirt and debris would readily build up on the brake drums.

Take some brake parts cleaner and run them through the unclean area if you wish to correct these issues. Furthermore, if the brakes are touching the drum while the wheels are turning, you might need to slightly adjust them.

3. Mazda RX 8 SE3P 2002 to 2008
Mazda RX-8 SE3P 2002 to 2008 by Hatsukari715. When the Mazda RX8 first left the production line, its braking system was excellent. However, after a while, owners noticed that the car was a little bit noisier than it was at first. At some point, it got too loud for people to keep driving. The brakes would creak, and the brake drums would quickly fill with dirt and debris.

7. Ignition Troubles

Along with the engine, of course, the RX8 has some issues with ignition. Drivers complained that starting their cars would take too long and occasionally would not even start. The car’s battery terminals or the cable connections leading to the battery were presumably defective, according to people.

The fluid level sensor located in the expansion tank has further general problems. This car is thirsty, therefore it will use a lot of gas to run efficiently. Owners grew weary of frequently adding just enough oil to keep their automobiles running.

Once you’ve eliminated every potential cause for your car not to start, double-check everything to see if you missed anything when trying to locate the issue.

8. Transmission Problems

The Mazda RX8’s transmission is its most problematic component, second only to the rotary engine. Owners discovered that the car transmission would not shift even after depressing the clutch pedal and attempting to move the stick shift.

For any car owner, this is hardly the ideal scenario! This led a lot of racing drivers to opt against using the RX8 models on their tracks.

In addition, the RX8 riders had concerning complaints during a race. They claimed that when they tried to put the car in first gear from a stop, the gears remained in place, making it challenging for the driver to accelerate.

Trying to determine the acceptable way for the gearbox to shift and the RMS level the engine is operating at could be the issue.

Additionally, the clutch connecting and shift cables on this model may require a lot of fiddling since they do need some adjustment. It can be nearly impossible to fix and modify the settings for sports cars in particular every time they accelerate.

9. Gear Problems

Automobiles aren’t made to endure forever. However, an automobile is designed to operate without any problems up until the point where the gearbox or transmission begins to deteriorate.

Due to its poor gear problem, the Mazda RX8 reliability is once again called into doubt. In this instance, gear slippage becomes an issue far more quickly. You must routinely check the transmission fluid and oil in any type of car. The RX8 is more suited for this.

A shortage of fluid or a hot engine can occasionally cause transmission fluid and oil burn, which makes drivers more aggressive on the road.

Additionally, metal fragments could be circulating in the fluids and beginning to deteriorate the engine and the moving components of the transmission. Make sure to check these fluids first if you are having trouble shifting gears.

You might need to check your engine, gearbox, and transmission for issues. Regular fluid inspection is important. Get the clutch checked as well if the gears begin to slip too easily.

10. Clutch Issues

Maybe racers have dreams about their vehicles struggling on the track with a dragging clutch. For instance, your car won’t have the necessary power to quickly elude the opposing force if you fully depress the gas pedal to prevent a collision but the clutch does not fully engage into gear.

Another illustration is when the RPM rises over normal when the car shifts into gear. Either the clutch doesn’t engage or it drags.

4. An RX 8
An RX-8 by Renesis / CC BY-SA 3.0. The rotary engine is the second most problematic part of the Mazda RX8 after the transmission. Owners found that even after squeezing the clutch pedal and attempting to move the stick shift, the car’s transmission would not shift. This is not the best situation for a car owner! Due to this, many racers decided not to use the RX8 models on their tracks.

When the driver presses the clutch pedal yet the clutch does not release from the flywheel and clutch disk, the clutch is said to be dragging. The car would refuse to change to another gear as the driver tried to do so because the clutch was unable to separate from the flywheel in time.

The cable that is attached to the clutch pedal perhaps coming free could be the issue. It should be fixed by tightening it. If issues continue, take your car to repair.

When your car struggles to change gears or makes odd noises while doing so, it’s time for a checkup. When changing gears, be aware of any sounds that could pose an issue because they could be resulting in minor gearbox damage.

11. Issues with Engine Lights

On the dashboard, engine light indicators are a crucial component. They alert you to problems that are developing inside your car so you may address them before more serious damage is done.

Some users said that their RX8 was having problems with these lights because the sensors were malfunctioning. After a diagnosis, an owner found that the issue might also be brought on by an aftermarket component.

Without having the car inspected by a qualified expert, it would be challenging to determine that the sensor is the issue. Every car owner should have an OBD-II scan tool.

Although you are now spending money, you will discover the advantages outweigh the expenses. This diagnostic tool will successfully inform you of the parts of your car that are acting erratically. The practical approach is quite effective.

12. Problems with Engine Noise

When operating an RX8, many users have also heard a faint buzzing or humming sound. A driver or racer may hear a clunking sound as they shift gears.

Although mechanical noises are common, we always advise having your automobile evaluated just in case. If you agree to let them fix your car if something goes wrong, several mechanics and auto repair companies will diagnose any problems for free.

Check the clutch cable for slippage, loose wire connections, leaks, and anything unusual before starting your RX8 again. You may tell when you need to stop by paying close attention to your surroundings and understanding the causes of clunking and humming noises.

You’ll be delighted to discover that many of your cars can be fixed by you with the aid of a few basic tools and the ideal guide, DIY enthusiasts. Take the risk instead of saving a few dollars; you can probably fix a few minor problems on your own.

Other Minor Problems Relating to the RX8

Apart from the significant issues outlined above, the Mazda RX8 reliability is in question due to a variety of minor issues. These tiny flaws can certainly irritate an owner, even though they are not as inconvenient as engine or gearbox issues. ‘Quirks’ to remember to include:

5. Mazda RX 8 40th Anniversary Edition

Mazda RX-8 40th Anniversary Edition by Owais Mohsin / CC BY-SA 4.0. The Mazda RX8’s dependability is once more questioned as a result of its bad gear issue. In this situation, gear slippage manifests itself much more quickly. Any type of vehicle needs routine transmission fluid and oil checks. For this, the RX8 is a better choice.

  • Unreliable Coolant Sensor
  • Non-operational back windows
  • Broken dashboard
  • Cup Holders Heating

How to Address Mazda’s RX8 Reliability Issues

1. Fuel Pre-Mixing

We advise pre-mixing the fuel before adding it to the tank because an RX8’s engine is known for guzzling fuel voraciously.

Simply add a little 2-stroke motor oil to the petrol tank when you fill it up to improve the lubrication of the engine seals and reduce oil usage.

The suggested ratio for the Mazda RX8 is 0.5 oz. oil per gallon of fuel. There are numerous video lessons available to assist you in getting started with this method because it is so well-liked.

The pre-mixed fuel could cause the stock catalytic converter to explode, so remove it before the procedure using a straight pipe. The vehicle would then stop passing smog as a result.

2. Change the Ignition Coils and Plugs

The replacement of the ignition coils, plugs, and wires is a further measure that may be taken to increase the Mazda RX8’s dependability. This is a rather straightforward procedure and a common piece of maintenance for most automobiles, but it’s especially important if you want the RX8 to survive longer.

3. Purchase a Cooling Fan Control Kit

We have already discussed the RX8’s propensity for high revs. Naturally, it increases the heat gradually.

A cooling fan control kit is an excellent alternative, but experts advise replacing the cooling hoses and radiator with aftermarket parts that flow a little more freely. With the help of this kit, you can modify the operating temperature of the cooling fan.

A cooling fan will activate at the factory settings when the engine temperature hits 206 degrees Fahrenheit. With this kit, the fan activates in high-speed mode when the engine temperature reaches 180 degrees.

Mazda RX8’s Advantages and Disadvantages


  • Although this car isn’t the fastest in the RX range, it feels incredible nonetheless. The RX-7 is conceivably the only model that can be compared.
  • Affordable. Renesis rotary engines are undervalued by the general public, thus used RX8 versions can be found for reasonable costs (particularly true for the U.S.).
  • Very stylish and traditional chassis. With the RX8, Mazda’s attention to detail in styling is evident. With its defined contours and clean lines, the design is refined rather than forceful.
  • Even an outdated model incorporates the most recent technology. includes proximity keys, an integrated sound system, and electric operations.
  • Superb sound.

6. Mazda RX 8
Mazda RX-8 by Shadman Samee / CC BY-SA 2.0. According to some users, their RX8 was having issues with these lights since the sensors were broken. After a diagnosis, an owner discovered that the problem might also be caused by an aftermarket part. It would be difficult to identify the sensor as the problem without having the automobile examined by a knowledgeable professional. An OBD-II scan tool should be available to every automobile owner.


  • Poor fuel efficiency.
  • The inside is very compact. Taller drivers might have their heads brushing against the cabin’s top while driving.
  • Zero payloads. Despite the attractive trunk, there isn’t enough room for anything other than a few groceries.
  • The car takes a while to accelerate because of its low-end torque. However, the acceleration is gradual.
  • The RX8 requires more maintenance than other vehicles from Mazda. Additionally, you are not given the option of clinging onto anything. The rotary engine could be damaged by one neglected oil change, and you don’t need anything else to exacerbate the unstable part’s condition.
  • Registration, insurance, and emissions. You will have to work on this paperwork every other year because the RX8 has some emissions issues, which increases the expense.
  • The radio lacks an AUX port.

How Long Can the RX8 Engine Last?

Regarding how long the typical Renesis rotary engine will last, there are several theories and solutions. Like any other engine, its service life will be increased with adequate maintenance and care.

That might imply 80,000 miles or less. Sadly, difficulties will arise if you don’t realize what you are getting into right away.

7. Mazda RX 8 Spirit R

Mazda RX-8 Spirit-R by Shadman Samee / CC BY-SA 2.0. Another step to improve the dependability of the Mazda RX8 is to replace the ignition coils, plugs, and wires. This is a relatively simple procedure and a standard maintenance task for most cars, but it’s crucial if you want the RX8 to last longer.

This is why maintaining a regular maintenance schedule is crucial for all vehicles, not just the RX8. We advise you to do that unless you can afford to rebuild an engine every two years.

Remember that the Mazda RX8 needs regular maintenance. It has a distinct “aesthetic” face value but will cost you a lot in the long run.

Choose a Mazda Miata or Honda S2000 if you’d prefer not to deal with that. Both of those are excellent options.

The Conclusion

With features such as a streamlined body and back doors that open from the rear, the Mazda RX8 was initially the ideal purchase for anyone looking for a beautiful and adorable family couple.

Perhaps in the process, the designers overlooked the quiet killer that affects the Mazda RX8 reliability and was installed under the hood. To put it simply, not everyone prefers rotary engines.

8. RX8 Reliability 9. RX8 Reliability

Mazda RX-8 SPIRIT R by Tokumeigakarinoaoshima / CC0