[rootcause]

Commands

/refuel - Starts/stops refueling your vehicle, needs you to be near a gas pump.
/arefuel - Refuels the vehicle you're in, can be used anywhere. (RCON Only)
/arefuelall - Refuels all vehicles. (RCON Only)

Consumption Rate

This script uses vehicle mass, speed and distance the vehicle travelled since the last consumption. For example a Landstalker going max speed with 500 meters travelled should consume 0.974717 Liters of fuel. You can modify it from line 335.

No-Fuel Vehicles

You can add any vehicle model to the switch/case in Vehicle_IsANoFuelVehicle function and they'll be a no-fuel vehicle which means they won't get affected by this script. Bikes are no-fuel vehicles by default.

Gas Pumps

You can add/modify gas pump coordinates from PumpData array. Default coordinates are taken from GTA SA IPL files so pretty much every gas pump can be used to refuel.

Credits

Emmet_ for Extended vehicle functions
Vince for Extended Vehicle Information
[HLF]Southclaw for Progress Bars v2
Incognito for Streamer Plugin
Zeex for zcmd

Notes

You can use the LITRE_PRICE define to change litre price. (Default: 3)
You can use the UPDATE_RATE define to change the consumption time, needs to be in milliseconds. (Default: 1000)
Since there are no gas pumps for boats AFAIK, so you might have to map some and add their coordinates to the PumpData array or you can make boats no-fuel vehicles.

Downloads

Mediafire || Pastebin