Hi SIFLIGINIUS.
I don't think your question is particularly relevant for this forum, but I will attempt an answer.
If your gauge readout is analogue, with a moving needle, then you don't need to "convert the voltage" at all. Just print a new scale for the gauge and stick it on top of the...
By the way, I think the Calculated Load Value could be a more accurate measure of fuel consumption on diesels.
According to ISO 15031-5 (equivalent to SAE J1979), for petrol (gas) engines the CLV is effectively (current airflow / peak airflow), and as reidh pointed out, the air-fuel ratio is...
So how do after-market trip computers like the ScanGauge calculate fuel consumption?
The ScanGauge web-site says that 99% of cars and light trucks report information on fuel consumption.
So I presume they are using generic OBD data.
But what PIDs and what algorithm?
And given the variations...
Thanks for the feedback.
I'm looking for a fuel consumption metric that will work for petrol (spark-ignition) and diesel (compression-ignition) engines using only generic OBD2.
What about PID $04 - Calculated Load Value?
This is returned as a percentage.
Any better suggestions?
The consensus seems to be that measuring the on-time of the fuel injectors is the way to go. But how to do that? As far as I know, the injector timing isn't available over OBD2 (EOBD).
An alternative approach I have seen is based on the fact that:
Fuel Flow = Air Flow / Stoichiometric...