Trying to figure out what the formula I need should be for the sensor, can anyone help me with the formula/equation please?
On the Autometer sensor the 240 ohms is the 0psi resistance and 33ohms is the 100psi resistance.
Here is a graph and some info from the web that someone else did on an Autometer sensor which may reveal some useful data
As you can see from the graph, the Autometer 2242 is a much better pressure transducer than the stock Fox sender. I ran a linear trendline and the sensor is pretty darned close to the line. The equation for the trendline is yPSI=108.4-0.56xOhms. Assuming the linear sensor performance continues to 100 PSI (which I must do since I have such a wimpy compressor) then you will see 15 Ohms at 100 PSI.
PSI Resistance in Ohms
75 70
70 73
65 79
60 85
55 95
50 105
45 113
40 120
35 130
30 140
25 148
20 156
15 170
10 190
0 267