What wire for logging Autometer fuel pressure?
I want to log the fuel pressure on my EIO on my scanner.
There are three wires going to the gauge. Red, green, brown.
There are three wires connected to the sender. Power, ground, signal.
After reading some posts here and on the hptuners forum, I thought I needed to tap the white signal wire coming from the sender, and should expect to see .5 - 4.5 volts for 0-100 psi. So I'm set up to divide volts by .04 then subtract 12.5. The setup graph shows this matches up to the expected range.
The scanner is showing 19.8 psi, which definitely isn't right.
Which wire should I be tied in to?
Hope this helps.
Wire should be the single lug on the connector (has two side by side above it).
The formula is "({Voltage}*25)-12.5
I read through the links, checked the pictures, etc.
Mine is different. It's from 2002 or so. Must be an older version. It still uses a separate controller box like the one shown on page 1 of the attached pdf. The date on these instructions is 2001. The newer instructions are dated 2002.
Decided I would just test all the wires and find it that way. Ends up the white signal wire from the sender is the right one after all. I just had a bad connection to it when I tapped it for the EIO.
The green wire from the controller has a similar signal, but the range is a little different. I didn't want to figure out/map that range, since the white wire is going to work for me.






