Rattling When Idle
Firstly, you need to check if the rattling occurs when your vehicle is idle. If this is the case, this could be a sign of 3 common issues:
1. Running problems from a catalytic converter
2. A spark knock problem
3. A collapsed lifter
Catalytic converter issues
If you hear a faint metal rattling when idle, likely, your catalytic converter isn’t running well. The catalytic converter controls the working function of your exhaust system issue and is not an engine issue. It helps your car to remove gases and keeps your exhaust from overheating. After some time, the catalytic converter can break down, causing the faint rattle sound you can hear at idle. You need to repair and change the catalytic converter to solve this issue and prevent running problems.
Spark knock is a combustion issue that usually occurs with a pinging noise. If you experience this sound, it is likely a cylinder issue that causes the fuel in your vehicle to burn unevenly. Spark knock is caused by overheating, gas issues, or simply incorrect spark plugs. Even though spark knock is a minor noise, it can lead to dangerous engine failure and needs to be treated promptly. You need to identify what is causing the spark knock issue and replace the spark plug to prevent failure.
Collapsed engine lifters
Engine lifters control the moving parts of engine valves. Lifters are kept running smoothly with the use of engine oil, however, oil levels can sometimes be affected, causing engine lifters to fail. Collapsed engine lifters occur mainly in older vehicle models, causing rattling when idle. Valves need either replaced or changed completely to keep engines running smoothly.
How To Identify The Noise
Is the rattling in your car coming from the interior or exterior? Here are steps on how to identify the noise and address it.
Rattling from a car’s interior
- Panic can cause us to miss even the simplest items. In this case, it could be your glove box. Make sure your glove box is firmly secured and ensure there are no items that can be rattling. If the issue is your glove box, the noise is likely a simple fix of an unstable glove box compartment.
- After checking your glove box, move to other compartments in your car. The rear can contain compartments and cup holders that you could’ve dropped or placed an item on and simply forgot about such items. It could also be loose compartments that have been subjected to wear and tear over time.
- Check your windows and seats. Often interior noises can be from a loose window or seats that are missing screws. If you have an older car, your car seats or doors could likely do with maintenance or a replacement.
Rattling from a car’s exterior
- Listen to the noises that occur when you apply your brakes. If the rattling noises occur with screeching noises, it is likely an issue with the brake pads. You may need to contact a mechanic to find out if you need to replace the brake pads or rotors.
- A rattle that comes with a roaring of the vehicle’s wheels can suggest tire issues or bad wheel bearing. Issues with wheel bearing need to be addressed promptly, especially if you tend to drive at higher speeds.
- Is the sound coming from under your vehicle? Sounds underneath a car could be an exhaust system issue. To check for exhaust issues, listen for a noise that resembles rumbling or the sound of rocks rattling. Some sounds could also be pipes or muffler issues.
Rattling When Accelerating
If your car rattles when accelerating, it can be caused by several factors that could potentially be dangerous or easy-to-fix solutions. The most common causes include:
1. Cracked flywheel
2. Loss of belt tensioner strength
A cracked flywheel could be a reason behind the noise. It is usually around the engine compartment and engages with the transmission as you accelerate. Tension occurs when the flywheel is cracked, causing the slight rattling noise that you hear. A cracked flywheel can cause transmission damage and lead to accidents should parts fall off. The flexplate can be replaced depending on how much damage has been done.
Belt tensioner issues:
If your engine rattles when accelerating, it could indicate an issue with the belt tensioner. Over time, belt tensioners lose their strength, and the timing belt starts to click as it moves. If the timing belt is not replaced, it could cause friction and engine failure.
SPECIAL INTEREST AUTOMOBILES is a Cambridge-based retail shop dedicated to serving clients with their car maintenance needs. If you hear rattling in your car, don’t delay. If you leave the problem for too long, it can fester into a bigger (and more costly) problem down the road. Our expert team of auto service technicians specializes in maintenance tune-ups, fleet services, repairs, oil change, tires services, and suspension services. No matter what the cause for your rattling, we can locate the problem and offer tailored solutions to ensure your safety.
If you experience rattling in your car, do not hesitate to give us a call today!