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Fuel pressure sensor
Posted: Thu Feb 16, 2023 12:40 am
by Awalkerch750
I have a three-wire automotive style fuel pressure sensor/sender 0-5 volt with signal wire. My Discovery Lite EFIS set to this style sender reads 7.7 psi with nothing hooked up. After attaching the wires to the RDAC the efis reads 4.2 psi. Using a manual gauge installed in the fuel line I know my fuel pressure is 42psi. Any help appreciated.
Re: Fuel pressure sensor
Posted: Thu Feb 16, 2023 1:29 am
by sparxfly
You need to switch the pull-up resistor OFF.
It is forcing full scale (5V) with an open input, and pulling the sensor reading higher than actual.
Re: Fuel pressure sensor
Posted: Tue Feb 21, 2023 7:25 am
by Bill Hertzel
Have you configured all the settings properly?
Menu>System Setup>Fuel Related Setup>Setup RDAC1 Senders>Fuel Pressure Setup
It sounds like the system thinks 5 volts = 7psi instead of 70psi.
Also, confirm your sender is 0.0-5.0v and not the more common 0.5-4.5v; it makes a difference.