Hello Everyone, This thread is only to help someone else with the same problem I had recently.

I own an 2009 RX8 R3 with 69000km (43000 miles) on it. A month ago I began to have some power loss at around 7000 rpm with no check engine and during the month, the power continued to degrade to a point that I was unable to go more that 5000 rpm and difficulty to drive the car at all. At that point I begun to receive check engine with P0411,P0410 and some misfire P0300.

I read/search every single thread here and went to a debug mode.

1- I changed the spark plugs with wires = didn't work !

2- I changed the coils with the D585 coils and 10mm cables = still no change

3 - With all the reading I begun to suspect the catalytic converter...

4- I removed the catalytic converter and heard rattle noise from it when I rotate it...Confirm the CAT was in pieces but in the middle of it. All that time I never received the P0421 saying my CAT was bad....

Fortunately my CAT was still on the 8 years or 128 000 km (80 000miles) warranty and will be replaced by Mazda at no cost.

I just want to thank all of you that took the time to put all the info in this forum that helped me resolved this frustrating problem.

Frank

 

What did the dealer need to confirm your cat was bad? Inspection alone?

 

Mazda diagnostic the car with their computer and also visual inspection

 

So lesson here is to always install a race pipe on a rotary car. #racecar #fuckemissions