OnEntityKill is called when you recall a vehicle.
so if you have "Remove Vehicles On Crash": true, each time you recall the vehicle, you have to rebuy it, as it thinks its crashed.

i made the following changes which seems to fix the issue

        private void OnEntityDeath(BaseCombatEntity entity, HitInfo info)
	{
            if (entity == null) return;
            Vehicle vehicle;
            if (!vehiclesCache.TryGetValue(entity, out vehicle)) return;
            vehiclesCache.Remove(entity);
            if (!configData.settings.notRefundFuelOnCrash)
                RefundFuel(entity, vehicle);
            if (storedData.playerData.ContainsKey(vehicle.playerID) && storedData.playerData[vehicle.playerID].ContainsKey(vehicle.vehicleType))
            {
                if (configData.settings.removeVehicleOnCrash)
                {
                    storedData.playerData[vehicle.playerID].Remove(vehicle.vehicleType);
                    return;
                }
                storedData.playerData[vehicle.playerID][vehicle.vehicleType].entityID = 0;
                storedData.playerData[vehicle.playerID][vehicle.vehicleType].lastDeath = CurrentTime;
            }

	}
        private void OnEntityKill(BaseEntity entity)
        {
		
            if (entity == null) return;
            Vehicle vehicle;
            if (!vehiclesCache.TryGetValue(entity, out vehicle)) return;
            vehiclesCache.Remove(entity);
            if (!configData.settings.notRefundFuelOnCrash) //on recall also.
                RefundFuel(entity, vehicle);
            if (storedData.playerData.ContainsKey(vehicle.playerID) && storedData.playerData[vehicle.playerID].ContainsKey(vehicle.vehicleType))
            {
                storedData.playerData[vehicle.playerID][vehicle.vehicleType].entityID = 0;
storedData.playerData[vehicle.playerID][vehicle.vehicleType].lastDeath = CurrentTime;
            }
        }​

Thx, fixed. xD