With time, the timing belt will begin to weaken. This will require a replacement. If the timing belt snaps, the valve timing can be disrupted. This can result in destroying the pistons and also the engine, causing internal engine damage. The timing belts connects to the crankshaft and camshaft. This helps keep them properly synchronized with one another.If they are off in one way or another, the engine can lose power. You might also notice wasted gas or performance issues. Replacing the timing belt occasionally is recommended for the performance of your vehicle. The belt sits behind the front of the engine. Typically, a lot of things have to be removed to get access to it. Many of those items that have to be removed are also normal-wear items, such as fan belts and the water pump.