I'm sure you must confuse with the gameplay

I tested the game at your location and everything was OK

If you don't touch anything the car runs at a 'medium' speed.
If you go 'left', you slow down the car, but if you don't touch anything, the car will go again at its 'medium' speed.
Now, if you go 'right', you accelerate the 'car', but again, if you stop to go right, the car will go again at its 'medium' speed.
In any case, if you don't touch the joystick, the car will run at its medium speed/position
Try it in Mame and you'll figure out the controls
