You didn't buy a Chevrolet for its low horsepower, chuffing idle, and misfiring, right? Then why are you living with these symptoms of a worn out Chevy timing chain? The Chevy timing chain found in most older design Chevy V6 and V8 engines is generally a durable component, but as it ages the clearances between the Chevy timing chain and the timing gears tend to grow. The result is that your car still starts and runs, but it just won't run well. Since the Chevy timing chain controls the motion of your camshaft, which is your engine's brain, it's no wonder your car or truck isn't performing up to snuff. Those of you out there with newer Chevy engines that use a Chevy timing belt, don't get too smug. While the Chevy timing chain may wear down over time, the Chevy timing belt just breaks when it wears out. Most Chevy engines just quit running when the Chevy timing belt (or the Chevy timing chain, in rare instances) breaks, but a few interference designs will self-destruct in this situation. The only way to ensure that your Chevy timing belt doesn't break is to replace it at the specified intervals, usually between 45,000 and 60,000 miles. There's no replacement interval for the Chevy timing chain, but it will let you know when it needs to be replaced. Your vehicle will simply refuse to be tuned properly regardless of what you do. So before you spend a bunch of money on plugs and injectors, be sure to check the Chevy timing chain for excess wear. A new Chevy timing chain along with new timing gears can make a huge difference in your car or truck's performance, while a new Chevy timing belt can provide the peace of mind you need to trust your vehicle again.