I just bought this obdII scanner from Harrison R&D at obdscan.net.
I got their OBD+CAN interface that works for all cars/protocols (IOD9141, VPW, PWM, etc) (USB).
I can connect to the vehicle and read all the data, etc, but not the Air Flow Ratio.

Their website says:
"Some 2001 and later cars, especially turbos, are using Wide Band O2 sensors...
Our OBDScan application will read these sensors and we provide a real time AIR/FUEL ratio meter"

My Question: Does the 2004 G35 Coupe have Wide-band O2 sensors?
If not, can I arrive at the A/F ratio using a combination of other OBDII data?
In general, what is the best way to measure A/F ratio?

Thanx in advance!

 

in general the best way is measure a/f is with a wideband.

 

Based on further research and the number of aftermarket wide-band o2 sensors available for sale (and the price of those systems),
I will have to assume that the G35 does NOT come stock with wide-band o2 sensors.
Unless someone tells me different.

 

i dont think it does.. everyone doing FI is installing them