Just purchased a 2007 Grand Touring Phantom Blue. This is my second RX-8. The first I purchased brand new in 2006 and wrecked/totalled in 2009. Anyway, I recently purchased this Grand Touring that is throwing these two codes. The dealer replaced the plugs, plug wires, and cat. He also said the O2 sensor would probably need replacing. Codes confirm that (I think?). Thoughts on the codes it's throwing? It drives wonderful and idles pretty damn good, just horrible gas mileage, and smell of gas when I'm stopped at a traffic light.

 

If it's getting bad fuel mileage and smells of gas, stop driving it now. Those are signs the catalytic converter is damaged or is being damaged and if it fails your engine goes with it.

The post-cat O2 sensor does need to be replaced according to this. Have the cat removed and inspected for internal damage.

While you are reading codes, can you read long term and short term fuel trim numbers on a warm idle (not driving, just warmed up and parked). That will point to any upstream issues that are causing poor mileage and running rich.

When you say horrible mileage, how horrible are we talking?

 

Did they replace the coils? Old OEM coils are known to fail and damage your cat.

The strong gas smell could also be from a leak between the exhaust manifold and the cat. Make sure it's bolted up correctly.

 

I bought a 04 rx8 for 500 bucks a few weeks ago.. I tried to code scan it as it dose not run.. I did a compression test on it came back fine... when I try to code scan it says can not communicate with pcm. I have tested all the relays so I guess I'm in need of a computer unless one of u guys know something else about it... anyway looking up computers for it the price is not terrible.. but I'm told after getting it I have to take it to a dealer and have them put it in and flash it... anyone know any web sights that will do this for a fee? Please email jbullet1988@gmail.com thank u