CEL but no code found with scanner
 

So I just got a 2004 used RX-8 from my cousin who takes care of this bad boy like nothing else. Yesterday the check engine light came on and I took it to Autozone and they ran it with their scanner but couldn't find a code. I also can't clear the CEL. Any suggestions?

get a better scanner

I've never heard of a CEL coming on without a code attached. Get it scanned again.

It can happen. It is also possible the scanner isn't ODB II CAN bus compatible.

When he plugged it in he was able to see things checking out saying that they were functional, just couldn't find a code.

it's happened to me as well.. Any idea why?

I have the same problem. My 8 randomly went into low power mode yesterday, the CEL light came on. I shut my car off, checked everything, and turned it back on. It ran fine, no weird sounds, nothing, but the CEL is still on. I took it to O'Reilly's and there scanner posted no codes.