Which parts fail
Components named in complaints (battery, alternator, wiring, ignition, instrument cluster, infotainment).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2004 Mazda RX-8 owners, lightly cleaned up (personal details are redacted by NHTSA).
Tl* the contact owns a 2004 Mazda RX-8. While driving 45 MPH, a burning odor entered the vehicle. The contact stopped the vehicle, lifted the hood, and noticed smoke. The contact observed that the wires underneath the hood were melted. The contact also smelled fuel coming from the rear of the vehicle. The vehicle was towed to an independent mechanic in louisville, kentucky who diagnosed that the wiring harness had melted due to a faulty electronic control module. The vehicle was repaired. The manufacturer and dealer were not contacted. The failure mileage was 136,777. Updated 10/17/17
I bought a car that had a recall of the air bag the passenger seat air bag had been deployed was told by dealer it was under recall.after checking with the dealer the side seat air bag was not part of the recall was not replaced or even looked at .so we took the seat out to see ant obvious issues and we found all the wires that plug into seat all way to under carpet against frame all the wires were melted.witch is an obvious manafaturing problem.we have read mupltile forums where tons of people have had same problem but yet no recall we could find on this issue.my mother is on oxygen and if my car catches fire to do this and no one looking into this it can be far worse.thier is another recall on front end suspsion that they are not willing to replace at this time.they tell me they are waiting to see if they come up with a better solution to fix it.im going to Mazda dealer tomorrow …
Electric-assist power steering, randomly in the parking lot the wheel will turn all by itself, one way turns easier than the other, sometimes you have no power steering and other times your steering wheel turns like butter, I live in the mountains with a very windy and dangerous roads, I've taken it to several mechanics finally one mechanic just unplug the wiring harness so there is no power steering. It is very scary to drive especially with a newborn baby. There are a lot of cars on the road with this issue I know 10 different people that have some sort of power steering issue. This is very dangerous and I'm surprised there is not a recall yet on it. …
My power steering goes in and out as it pleases; only works when it wants to and cuts up when driving and had to turn off car to make it work to only make it repeat again. Does this only when driving. And not safe for anybody who is dealing with the no powersteering issues or have steering but with many faults that can lead to accidents/death Mazda fixed others by wire tapping all deleting the powersteering connections. But only having the issue later down the road they did this around February/March of last year and had in and out powersteering after 3 month of their repair.
Tl* the contact owns a 2004 Mazda RX-8. While attempting to start the vehicle during cold weather, the motor flooded which caused the starter to fail. The failure recurred multiple times intermittently. The vehicle was taken to a dealer for diagnostic testing. The vehicle was repaired, but the failure recurred. The vehicle was taken to the dealer. The starter was replaced, but the failure recurred. The VIN was unavailable. The manufacturer was notified of the failure. The approximate failure mileage was 10,000.
Tl* the contact owns a 2004 Mazda RX-8. While driving 60 MPH, the vehicle stalled when shifted into neutral and the instrument panel lights illuminated. The failure recurred numerous times. The vehicle was taken to a dealer. The technician diagnosed that the air condition pump was defective and needed to be replaced. The vehicle was repaired; however, the failure recurred. The manufacturer was not made aware of the failure. The approximate failure mileage was 160,000.
Tl* the contact owns a 2004 Mazda RX-8. The contact stated that the entire center console overheated to the point that it was unable to be touched. The contact mentioned that the passenger side air bag cover was bulging and could crack at any moment. The vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure. The failure mileage was 80,010.
I purchased my 2004 Mazda RX-8 in March 2005 and problems with the check engine light coming on did not start until April 2006. At that time the car had approximately 26,000 miles on it (I have a long commute 90% of which is freeway). The first several times back to the dealer minor things were adjusted or cleaned such as the spark plugs and a small valve a kit to a butterfly valve in a carburetor engine. Eventually the valve was replaced, but the light still came back on. In fact, on one occasion the car was pulled out of the shop doors pronounced fixed and upon my starting it again the light was back on. Eventually Mazda approved that the intake manifold be replaced, which it was. The check engine light has stayed off since that replacement (about 3-months) , but other problems have arisen. …
Problems with rotary engine starting. Usually happens at a temperature below 25 degrees fahrenheit. Poor ignition system for colder weather. I have had issues with it each winter I have owned the car(2004 to present day). A trip to the dealer has been necessary each time and while the warranty is still valid, this is an inconvenience but it's after the expiration is when I worry. A recall was noted and repairs were completed the fall of 2006 but the same thing happened yesterday. This recall included spark plug replacement, battery replacement, starter motor replacement, and reprogramming the onboard computer chip for ignition changes. The new starter motor made significant changes to starting time but didn't change it's condition in colder weather. The Mazda dealer has been little help in resolving the situation. …
I have been going back and forth to the dealer for my rx8's power steering failure while driving at various speeds. When it shut off twice of the many times, it pulled my car to the hard right and I almost ran off the road because of it. The dealership charged me the first time to replace the battery terminal because it was loosing power to the steering unit. Then multiple times later, hundreds more, they said that repairing the wiring harness connectors was recommended by their tech line and they said that May not be the last thing needed. First of all, the dealership, heritage Mazda of lutherville, md, seem to be working hard on this problem, but this truly is a traffic safety issue and its costing me hundreds in a shot in the dark to fix the problem. …
Electrical complaints in other RX-8 years
Frequently asked questions
How common are electrical problems on the 2004 Mazda RX-8?
NHTSA has 33 complaints about the electrical system of the 2004 Mazda RX-8, 7% of the model year's 490 complaints. The component named most often is 12v/24v/48v battery (2 mentions).
Is there a recall for 2004 Mazda RX-8 electrical problems?
No. NHTSA lists no electrical system recall for the 2004 Mazda RX-8, though it has 10 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2004 Mazda RX-8 electrical problems start?
Half of the complaints with a recorded mileage happened before about 41,000 miles, and 33% before 25,000 miles.
Is it dangerous?
Owners linked 0 crashes, 1 fire and 1 injury to electrical system problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.