[zeniac]

AEM UEGO on 02 spec V w/ Turbonetics kits.

At Idle condition, no load (RPM aprox. ~ 700):

From cold start, AFR numbers were between 14.x and 15.x (I don't remember the exact decimal values because it was bouncing ever so quickly). I searched on Google, I understand this is normal. Right?
When warmed up, AFR numbers were between 17 and 18. Wow! The engine is not under load. Is this much too lean at idle?

Noted: If the engine is under a slight load (i.e rear defroster and heating vents are active), then AFR is around 14.x to 15.x.

AFR values are between 11.x and 14.x with load (regular driving and throughout RPM band).

I have the turbo kits for six months, and the engine does not exhibit any sign of malfunction.
Any correlation between octane grades and AFR values? ambient temperature? barometric pressure?

[Robert]

Typically what I have seen when the ECU is running the car that lean at idle is that the ECU is overcompensating timing for additional fuel from the larger injectors. On my 350Z the AFR would typically be in the 14-15:1 range with occasional moments of running in the 17s as the motor fought to keep the motor stoich with the larger injectors. Never caused an issue on my car after 75k+ miles.