FUEL ECONOMY GAUGE (HELP)

Hello,
I bought a fuel economy gauge for my 240 and it does not have
instructions on how to set up the wiring and tubing. I can remove
and reinstall the dash cluster w/o any problem. It is the wiring and
vaccumme that I need help with.
Please if you know how ....HELP ME.
Joseph Segura

 

What year is the car? Pre-'86 used a cable driven speedo, post are
electronic. Also what sort of guage is this? Do you have a link to the
manufacture?

 

Sounds like one of the old style gauges popular in the 50's and
60'sthat was merely a vacuum gauge with economy markings on it.
Running the vac line using a Tee fitting to a "live" vac line under
the dash should work. I would then guess it has two wires (black and
blue...?). One is a ground (black) and the other can be wired to the +
lead of any dash light so the gauge can be seen at night and dim with
the rest of the dash. This is all a guess since you gave so little
info to work from.