One of the earliest signs of a failing serpentine belt is a high-pitched squealing or whining noise, especially during engine startup or when turning the steering wheel. This noise is typically caused by the belt slipping on the pulleys due to reduced tension or deterioration.
There should be no movement or play from side to side. Misalignment – Misaligned pulleys will cause belt chirp noise problems and are caused by worn bearings. Cracked or Broken Pulley – Check for obvious physical damage.
Firstly, the most common sign of a bad tensioner is noise from the belts or the tensioner itself. Squeaking or squealing may occur, especially during startup, indicating a loose tensioner. Additionally, a worn-out tensioner pulley or bearing can produce a grinding noise. Unusual Wear Patterns.
Common symptoms of a malfunctioning idler pulley include corrosion on the pulley's surface, chattering and squealing noises, and slow spinning.
The symptoms will look like the timing belt isn't working. Engine Misfires: A worn-out timing belt will throw off the timing of your car's engine. This will cause it to misfire, and your car will struggle to start. The same thing will also happen if the timing belt is loose.
The engine belt or chain loops under or around the idler pulley, creating a continuous loop that allows the belt to move freely. The tensioner pulley helps keep the chain or belt tight, so that it can transfer motion and power efficiently from the crankshaft to other components in the system.
Rough Idle: The crankshaft pulley is subjected to a high level of stress as the engine is idling. A bad crankshaft pulley can make the engine idle rough. If you notice that the engine is idling unevenly, but you don't feel any misfires or combustion problems you should probably check the crankshaft pulley.
It typically takes about an hour to replace the serpentine belt, and if you know some car repair basics, you could change the belt yourself.
When a timing belt tensioner fails, it loses tension. As a result, the timing belt becomes loose and the valve timing can be thrown off. This leads to engine performance issues. So if any suspicion arises that the timing belt tensioner has failed, it's important to check the tensioner and replace it if necessary.
While a bad serpentine belt might not directly affect the engine's ability to accelerate, it can indirectly impact performance. If the belt fails and the alternator stops charging the battery, the resulting electrical problems could affect the vehicle's overall performance, including acceleration.
A bad crankshaft pulley or harmonic balancer can cause symptoms like engine vibration, abnormal knocking noise, inoperative engine accessories, and engine failure.
If you choose to have a professional replace your car's serpentine belt, you can usually expect to pay somewhere between $150 and $250 to get the job done.
An idler pulley is expected to wear over time, and eventually the pulley will fail. Replacement intervals for idler pulleys vary, but are usually within the 50,000 to 100,000 mile range. Replacement often coincides with expected serpentine/accessory belt replacement periods.
If the tensioner fails, it will no longer hold tension on the timing chain. Depending on the situation, this can lead to a rattling sound, but it could also allow the chain to jump and cause the engine to shift out of time. In that case, you may experience backfires and the check engine light will usually come on.
You shouldn't continue to drive with a faulty timing belt tensioner. This can result in severe engine damage and might leave you stranded.
A failed tensioner will cause the timing chain to be loose, which can result in a rattling noise coming from the engine. If the engine has hydraulic tensioners, you might notice that the noise is most prominent upon start-up when oil is just beginning to circulate throughout the engine.