The junkyard is a random encounter along routes that consists of a locked compound with one large building and many piles of cars around it. Between some piles are shelves that have a chance to spawn components for your car.
The gate to the junkyard is opened by adding the missing pieces to the broken car near the gate, then pulling the lever in the engine bay. Batteries and fuel will be discharged by 10% and consumed by 1 liter or the carburetor will be broken! respectively when the gate is opened, but otherwise parts are not damaged, and may be removed from the car as soon as the gate begins to move.
Sometimes all parts will be installed in the half of a Laika, you will need to add fuel to the tank installed if not already there. The Junkyard is usually represented on the route options as a ? symbol.