Analog data off.

[electricmarquis]

My 0-5 volt wideband seems to be off. Its average reading on the gauge is 14.7 which is right. The data log recorded with intunes average is 13.7. Right about a point off. The math reads out to be .98 off. The voltage scale from AEM is tabled at .5v-4.5, not 0-5.

AFR (Gas) = (2.375 * Volts) + 7.3125
Voltage AFR (Gas) AFR (Lambda)
0.5 8.50
1.0 9.69
1.5 10.88
2.0 12.06
2.5 13.2
3.0 14.44
3.5 15.63
4.0 16.81
4.5 18.00

So with the above math I tried this as the lower range 7.3125 and 19.1875 as high. Any suggestions?

[electricmarquis]

I changed the wiring a bit to see if the output voltage was the culprit. The wideband has a ground for its power and a ground for the ananlog outputs. These were landed on the same ground source. I seperated them and isolated the analog ground to just the intunes data cable. I will see if this changes the output voltage from the gauge to see if the scaling was off or the voltage output to scale was skewed from ground loops etc.

[electricmarquis]

Well that was a failure. Numbers in the 17ish area now while idleing at 14.7

[electricmarquis]

BTW.

I solved this. The math worked. It was the port on the bottom of the intune. It was not allowing the plug to seat with full contact of the probe. I switched to the Trinity so I could log minus the laptop in the car.


I also talked completly to myself in this thread.

[jwdemon]

Sometimes it helps to just talk things through!