I bought my RX8 about a week and a half ago. (16 miles off the lot :P ) I've noticed a little clunking noise when backing. It happens about mid backing process. It's not when I put it in reverse or when I brake, but usually when I release the clutch to let it roll back. I will note this to the dealer when I take it in for it's 2 week once over, but I wanted to double check that this should not be happening. Other than this, and the fact that the dealer put 30PSI in the tires making the tire pressure meter go insane, I'm a proud new owner so far.

Oh...and I read there was supposed to be a 8500 RPM "tone". I know I'm not supposed to be running it at that, but sometimes you can't resist. Anyone else missing their tone?

 

Make sure your windows are up and the stereo is turned off. The tone is not all that loud so it can be drowned out by other noises.

 

I wouldn't be going higher than half of that rpm for the first 600 miles. Do a search on breaking-in the rotary. You'll have plenty of time after that for play. The alarm is very subtle and is not all that noticeable when combined with the other noises being made at that rpm.

The abs does a self-check when the car first starts rolling, the first time after you fire it up. I think it might also do it in reverse - not real sure. It's that "chunck" sound that you hear. Sounds pretty nasty, but it's not. It's normal and good.

I think 32 is the correct psi and 30 should not be cause for the tire pressure alarm to sound.

 

Racer X is right - the "clunking" you are hearing is the ABS self-check. It will occur after the car is started and is initially driven to 1-2 mph (forward or reverse).

To be sure, do this: Start the car and back it up and note the "clunking" sound. Stop, pull forward, and then backup again. You probably won't hear the sound the second time (because the ABS check is complete). If you do, then there might be an issue...