I'm curious to see my air-to-fuel ratio since I've done a few mods (10% pulley, and 3.5 inch intake). Does anyone know how to see your AFR in real time? I have a Bluetooth OBD-II scanner and use Torque (Lite) app to view the info on my phone. Has anyone been able to do this on an app with a bluetooth OBD-II scanner? Would you say that it is accurate?

Thanks.

 

With a digital meter on the return signal back to the ECU you should see 0.50 volts DC going toward 5.0 on throttle up . On a graph you can see the flowrate ( specific to each MAF sensor ) There is one for the X300 .

On the ELM327 based devices the MAF is sometimes off by a factor of 10 or 100 .

At idle for a 4.0 liter engine at 650 RPM should read 4.0 grams / second ( seems low to me )

 

Or go to a dyno place that measures it as you rev and prints out a graph.

 

Lady Penelope,
Interesting, but how do you correlate voltage to AFR? Is there a reference sheet to look at?

JagV8,
I may look into running a dyno. I thought there'd be an easier method than that though.

 

There was a reference chart voltage vs. MAF for the X300 MAF meter different then yours . If you extrapolate the data points out as you will be above the data field keep in mind the saturation curve .