(Solved)How can I know what I need to deactivate the particles when it touches the ground?

Hello, well that I want the particles of fire to be deactivated when it touches the ground, I have tried many ways, but without result, how could I do it? I'm very stuck Thank you

local UserInputService = game:GetService("UserInputService")
local ground = game.Workspace.ground
local car = game.Workspace.car
local sound = Instance.new("Sound", script.Parent)
sound.Name = "engine"
sound.SoundId = "rbxassetid://532147820"
local wheel1 = game.Workspace.car["FrontR"]
local wheel2 = game.Workspace.car["FrontL"]
local mult = 1.30 
local maxpitch = 3.00 
local idlespeed = 1 
local debounce = false
local fire = game.Workspace.car.fire.Fire
fire.Enabled = false


if car.PrimaryPart ~= nil then

    car.PrimaryPart.Touched:Connect(function(touched)
        if touched.Parent ~= nil then
            UserInputService.InputBegan:Connect(function(input)
                if input.KeyCode == Enum.KeyCode.W or input.KeyCode == Enum.KeyCode.A or input.KeyCode == Enum.KeyCode.D or input.KeyCode == Enum.KeyCode.Up or input.KeyCode == Enum.KeyCode.Left or input.KeyCode == Enum.KeyCode.Right then
                    fire.Enabled = true
                end
            end)
            UserInputService.InputEnded:Connect(function(inputEnd)
                if inputEnd.KeyCode == Enum.KeyCode.W or inputEnd.KeyCode == Enum.KeyCode.A or inputEnd.KeyCode == Enum.KeyCode.D or inputEnd.KeyCode == Enum.KeyCode.Up or inputEnd.KeyCode == Enum.KeyCode.Left or inputEnd.KeyCode == Enum.KeyCode.Right then
                    fire.Enabled = false
                end
            end)
        end
    end)

end


car.PrimaryPart.Touched:Connect(function(touch)
    if touch then
        if touch.Parent ~= ground then
            print("false")
            sound:Play()
            sound.Looped = true
            sound.Volume = 1
            while true do
                wait (0.05)
                local wlsp = ((wheel2.RotVelocity + wheel1.RotVelocity)/2).magnitude
                local wlsp2 = ((wlsp / 200) + idlespeed) * mult
                if wlsp2 < maxpitch then
                    sound.Pitch = wlsp2
                else
                    sound.Pitch = maxpitch
                end
            end
        end
    end
end)
ground.Touched:Connect(function(touch)
    if not debounce then
        debounce = true

        if touch then
            if touch.Parent ~= car then
                print("true")
                sound:Stop()                

            end

        end
        wait(2)
        debounce = false

    end
end)