I only picked up my RX8 late yesterday afternoon. Took for a run on some back roads in the Gold Coast hinterland late last night, awesome.
Q1
No AC on last night, drove home from work this arvo AC on, ENGINE CHECK LIGHT CAME ON??
I think idle speed is a bit low with AC on, would this cause check light to come on?
Car is running like a dream, idles nicely without AC on.
Q2
Where should oil pressure sit?
Mine is about 2 bars over halfway.

Oh, it's series 1 6sp, 6port.

Cheers
Pete

 

Welcome.
AC problems won't cause a CEL. Get your codes scanned to find out what the problem is.
Oil pressure sounds normal.
Read the new owner stickies if you have not already.

 

The CEL is entirely emissions related. There are over 100 different codes it could be. Without the code behind the CEL, we can't do anything more but throw random guesses at you that are probably inaccurate.

 

Thanks, it is weekend here.
I will get diagnostics done Monday.
Need to find reputable rotary specialist on the Gold Coast, Australia
Anyone got recommendations.

 

In the US, most auto parts stores will read the codes for free. Not sure if it is the same there.

Alternatively, you can buy a bluetooth OBD2 adapter, connect it to your smart phone, download an OBD2 app, and read the codes yourself, along with a large number of other engine data parameters. You can get it all for less than a single diagnostics fee from any shop, and be that much more empowered to solve issues.