One problem related to manifold/header/muffler/tail pipe has been reported for the 2005 Mazda RX8. The most recently reported issues are listed below.
Hi, I purchased my 2005 Rx8 new in December of 2005. I have 38000 miles at present time. My vehicle has been towed three times due to stalling. I have had my vehicle in for all recalls and it has passed all test. I am still having problems with engine stalling while driving. My vehicle also back fires at times blowing black smoke from tail pipes. I have serious concerns over the safety of my vehicle due to the known fires caused by the rotary engine. I have phoned and visited many dealers to see if Mazda has issued a buy back or trade due to issues with the Rx8 and they have all replied with "sorry, but we can sell you a different Mazda at retail". I have had my vehicle to the Mazda repair shop so many times that I no longer even bother to take it in because I always get the same answer. I really just want my car fixed or something else to drive that is safe. I think Mazda needs to recognize that there is a real safety issue and peoples lives are in danger. The issues with my car are so many that I do not like to drive it. Currently the check engine light stays on. Please feel free to contact me for further issues with this vehicle.