What causes a belt pulley to make a rattling noise?
Symptom 1: Squealing, rattling, or chirping. When the tensioner or tensioner pulley fails, the loss of tension can cause the belt and pulleys to make high-pitched rattling or chirping noises. If the pulley bearing completely fails, it can also cause a squealing or even a grinding noise.
What does a loose belt tensioner sound like?
If the drive belt noise resembles a squeal or a squeak, it is possible that the belt tensioner is loose. This is especially the case when starting the engine first thing in the morning. Since the tensioner is not able to maintain the correct tension on the belts, it produces a squealing or squeaking sound.
What makes a belt sound like a squeal?
If you have belt noise that sounds like a squeal or chirp, you’ve got an underlying problem that must be fixed. The #1 cause of serpentine belt noise is a worn automatic serpentine belt tensioner. Most people blame the belt and replace it only to find the belt noise returns.
What causes excessive noise in a timing belt?
Improperly tensioned drives will more likely generate noise. Timing belt tension should not be too high or too low. Too low a tension can also lead to shortened timing belt life or ratcheting, while too high a tension will add undue stress to bearings, shafts and other related components.
When does a car make a rattling noise?
You may hear them when you start your car, when you drive it or when you apply the brakes. They may occur only when the engine is cold, or when it’s fully warmed up. Rattles may happen only upon acceleration, deceleration, going over bumps, rounding a corner, or during some other specific set of circumstances.
Why does my catalytic converter make a rattling noise?
The converter can be damaged by thermal shock or an impact, which can cause part of its internal structure to break off and cause a rattle. In extreme cases, this can sound like a box of rocks being shaken. The converter doesn’t fail by itself; something has to cause it to fail, and that should be identified before it is replaced.
Why are my heat shields rattling under my car?
These heat shields are made of thin pieces of metal, and are placed between these components and the underfloor of the vehicle. They have become a common source of rattling noises under the car. Over time, heat shields can rust out or become loose and get detached from their mountings.