Well, I have worked on it and so far I'm going pretty good, although there is something which doesn't makes too much sense.
I have custom movement.
If up is pressed, move up
if right " ", " right
if left " ", " left
when up release it goes down.
Have my collisions, my speed meter, and some other stuff, but was working with the fuel. I wanted that when the keys were pressed and the car wasn't parked the fuel went down, and it works, but not the why I would like. I made this event
If up key pressed OR left key OR right key: KeyPressed variable would be Yes.
Else: It would be No
At first it didn't looked like it worked, so I made a text that tell me whether it was on Yes or No, and what happen is, that is whether the speed toward the direction that it takes and not if the key is pressed, if the car is going just down the KeyPressed is No, but if the car is going to the right despite of not having the right key pressed, the variable is Yes. Why does this happen?
Also about the way the fuel drops, it does it just perfect.
Here is the example: