What you have is an Emmegas lambda controlled single point system. The gauge on the tank appears to be showing that it is empty so a bit of gas would be a good idea. As long as you get some in, even a fivers worth would be enough. That would work out to about a gallon and a half, plenty enough to test it but not so much that it'll take a week to vent it all out in case you have to.
It will have been set to changeover to gas when conditions are right. That would mean it will need to be seeing pulses from the ignition system to tell it the engine is running and that the revs are correct. Usually it will be set to change over on deceleration at a certain revs, maybe 1,500, maybe 2,000 rpm. So it will start on petrol and then change over when you blip the throttle. At that point you will see 12v appear on the solenoids, one on the tank and another on the vaporiser. If you test resistance to earth on the live side of one of the solenoids, you should see a resistance of around 8 Ohms as each solenoid coil should have a resistance of about 15 ohms each.
'96 Saab 900XS, AEB Leo, sold
'93 Range Rover 4.2 LSE, Lovato LovEco, sold
'98 Ex-Police Range Rover 4.0, Singlepoint AEB Leo, my daily motor
'97 Range Rover 4.0SE, eGas multipoint, a project.....
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