Thread: EFI/LPG controller, Info Wanted

I've just gone through similar with my RR and re-wiring the LPG switch and solenoids.

Unless you find a brand name, it will be a bit difficult. Even with the makers website it was a problem finding a wiring diagram.

However, provided it's a 'simple' gas system (ie non-electronic gas mixer) the wiring should be similar:
1. 12v feed from ignition (Red)
2.Ground(black)
3. Feed to gas tank sender (green and white)( maybe two wires to one end of the sender)
4. feed from coil to dash unit (brown)(for cutoff if you stall for whatever reason- could be adjustable via trimpot at rear of dash unit)
5. Gas feed cutoff solenoids (blue)( I use a relay as there are 4 to power)
6. EFI cutoff (?)( varies with installer - mine interrupts the overspeed/vac safety relay under the MAF - run off the cutoff solenoids)
7. Power to petrol cutoff relay (yellow)( Mine cuts the fuel pump power when on gas)

Within your dash unit may be a delay circuit like the interior light - mine starts on petrol for about 3 secs whilst the gas circuit is also on too, but the delay is a relay next to the converter.

Of course your system could be completely different.