Signs of a Failing Timing Belt

Your timing belt is one of the most crucial components of your vehicle. This small, seemingly unimportant rubber belt is actually a finely tuned part — its teeth orchestrate the timing of rotations of the camshaft(s) and crankshaft, and it may transfer power to other parts of your engine (such as the water pump and the oil pump). As such, a damaged timing belt will hinder the performance of your engine, and a snapped timing belt will render your vehicle undrivable. And unfortunately, both damaged and broken timing belts can wreak havoc on your engine. That’s why it’s so crucial to regularly swap out your timing belt, ensuring that your crankshaft and camshaft(s) are in sync, among those other systems that the timing belt may manage.

So, how do you know when it’s time to replace that old timing belt? And what are some signs that your timing belt is damaged? We’ve addressed those questions below, so that you can rest assured your engine will run smoothly for tens of thousands of miles.

Recommended Timing Belt Replacement Intervals

While you may ask yourself: Why can’t I just take a look at my timing belt to see if it’s in good shape? You should know that your timing belt is contained within the front cover of the engine, which means that it isn’t readily visible when you pop the hood on your car. To observe the timing belt, you’d actually have to disassemble quite a few central components on your engine — which is why this task is best left to professional mechanics. It’s also the very reason why it is recommended that vehicle owners regularly swap out their timing belts. Every vehicle make and model has a recommended timing belt replacement interval that car owners can follow to ensure that their timing belt doesn’t become damaged or snap while their on the road.

Your owner’s manual is the best source for information about the recommended interval for a timing belt replacement. If you can’t find your owner’s manual, check online for your specific make and model, or consult your mechanic. For older models, many timing belts only last about 60,000 miles before they become a liability. For newer vehicles, your owner’s manual may only recommend a replacement every 100,000 miles.

That said, it’s best to remain wary that your timing belt may become damaged or snap at mileage less than the recommended exchange interval, so it’s in your best interest to remain cognizant of signs of a failing timing belt — we’ve listed a few noteworthy signs below.

Signs of a Failing Timing Belt

Strange Sounds: If you have a strange noise coming from under the hood, it’s never a good sign. While it’s not always an indicator that your timing belt is failing, a strange noise may be caused by a belt that’s slipping, rubbing, or approaching its breaking point. Keep an ear out for screeches, squeals, and whirring noises. You may even hear ticking emanating from your engine compartment. These noises are most common right when you start your car, and you may notice them as you accelerate. In some instances, you may notice noises from your engine compartment as you idle as well.

Slipping During Acceleration: Does your vehicle feel off as you push the gas pedal down? If you’re accelerating, yet your engine seems slow to respond, then your timing belt may be to blame. If your timing belt is missing teeth, or it has stretched in size, then it may slip as you attempt to accelerate. These slips are a bad sign, and they may cause damage to your engine, so it’s best to bring it in to an auto shop as soon as you notice. Slipping is especially common when your engine is running between 2,000 and 4,000 rpms, as you accelerate, and as you shift.

Thick Exhaust: Thick plumes of exhaust smoke may be an indication that your timing belt is worn down. Since a bad timing belt may cause your pistons to misfire, your engine won’t burn its fuel efficiently. Subsequently, you will smell unburnt fuel, and you will see plumes of smoke pouring out of your exhaust.

Not Starting: Engine not turning over? Your timing belt may be the problem. Since your timing belt keeps your pistons firing properly, a damaged belt will keep your engine from turning over. When you notice that you can’t start your vehicle, don’t keep trying. You’ll strain your engine components and starting system, and you can actually cause more damage if you do manage to start your engine with a faulty timing belt. Instead, tow your vehicle into an auto shop for a diagnosis, and, if your belt is the source of the issue, a timing belt swap.

Complete Failure: If your timing belt rips or slips off its gears entirely as you’re sailing over the tarmac, then you’ll notice. A complete failure is unfortunately, usually catastrophic, and its likely that your engine will be totaled. A complete failure often results in bent engine valves, damaged cylinder heads, a damaged camshaft, and it may cause damage to the piston and the cylinder walls of your engine. The engine will make loud noises if your timing belt breaks, and your vehicle will be completely undrivable. Obviously, it’s best to avoid a complete timing belt break or slip, since it usually results in costly repairs.

Now, take note, all of these indicators may be caused by other issues within your engine, so we’ll have to assess your vehicle to locate the true source of any issue(s) that you may be experiencing.

Count on Thompson Import Repair

If you’re curious about your timing belt, or you think it’s time for a replacement, we’re here to help. Thompson Import Repair proudly provides timing belt replacement services for a variety of vehicle makes, including Acura, Honda, Lexus, Mitsubishi, Subaru, Toyota, and more. Our auto shop is conveniently located in Englewood, and we happily serve our neighbors throughout Denver. Get started today by stopping into the shop, or reaching out to us.

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