If your car is making a sizzling or hissing sound after the engine is shut off, then chances are something in the engine bay is leaking. You might be able to determine the source of the leak with a quick visual inspection, but be careful! Leaking fluids and air could be dangerously hot or harmful to touch.
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Why does my BMW make noises after I turn it off?
It’s the water pump, it stays on for a while to help cool the turbo’s down when you shut off the car. Pump circulating coolant to cool down turbos. That’s why we don’t require turbo timers. Its normal, nothing to worry about.
Why does my car sound like its releasing air?
Constant circulation of air and cooling fluid through your car’s engine can cause small cracks in hoses, breaking their vacuum seal. The whistling sound you are hearing could be air escaping through these holes.
Why does my car engine make noise after I turn it off?
If your car makes a metallic clicking sound after you switch off the engine, it’s just the sound of the engine cooling down. It’s nothing to worry about and will stop of its own accord fairly quickly.
Can I drive my car if it is hissing?
If you can hear hissing coming from the front of your car, it’s likely that the engine is overheating. Make sure you stop driving as soon as possible and allow your engine to cool down for at least fifteen minutes before investigating.
What makes a hissing sound?
The sound you make when you hiss โ also called a hiss โ sounds just like the word itself. In fact, you can’t say the word without hissing. This type of sound is also known as sibilance, a consonant that’s pronounced when a stream of air passes through teeth that are touching or close together.
Why is my car making a fan noise?
Worn bearings, bent or broken blades, and unbalanced rotating assemblies can cause a fan to screech, howl, or otherwise make noises it shouldn’t. Fortunately, switching out a worn fan for a new one isn’t a huge ordeal.
Why is my BMW making a whining noise?
One thing that could have happened to cause this disruptive sound is a loose belt. Or a leak within the power steering system can also cause excess friction, producing this sound. Either way, it’s best to have a professional inspect and repair your power steering system.
What does a vacuum leak sound like?
Hissing or Sucking Noises Usually, when the leak isn’t too bad, you will hear hissing noises coming from the engine. This may also sound like whining sounds or whimpering sounds. For more severe vacuum leaks, the noise is sucking or suction, much like a vacuum cleaner.
Why do I hear air coming from my tire?
One way to check for a leak is to listen near the suspect tire. Sometimes you will be able to hear the pressurized air escaping from the small hole in the tire. It will sound like a faint hissing noise. If you hear this, make an appointment with a mechanic to have your tire problem inspected and repaired.
Why does my engine sound like a vacuum?
If your car’s engine suddenly sounds like a vacuum cleaner, you have a serious vacuum leak. All vehicles have combustion engines, and producing combustion creates vacuum pressure. This pressure is routed throughout your engine so that it can power components such as the power steering pump.
Can you drive with a vacuum leak?
Driving with a vacuum leak should not be done because it causes a loss of power to your engine. This can be unsafe while driving down the road, especially if the leak increases as you are driving.
How does a car sound with no coolant?
When your coolant levels are too low, your radiator will fill-up with air. These air pockets in your cooling system will cause a gurgling or growling sound. Leaks commonly sprout from cracked hoses or a leaky water pump gasket and should be checked right away to prevent engine damage.
Why does my car AC sound like its hissing?
Hissing or Whistling It could be the sound of refrigerant gas in your expansion valve, for example. But a persistent hissing or whistling sound could be a sign of a refrigerant leak. A refrigerant leak could occur in your refrigerant lines or in your internal valve.
Why is my air vent hissing?
A hissing noise coming from your HVAC system is not something to be overlooked. Among the possible causes are leaky refrigerant lines, an internal valve leak or a serious problem with your compressor. If the hissing noise is coming from your ducts, then you may have leaky air ducts.
Why does it sound like air when I press the gas?
Usually this type of noise in an indication of a exhaust leak or a vacuum leak due to a broken or disconnected vacuum line. If you also notice that your car is slow to accelerate or is running rough, then it is likely that one of these items is the root cause.
What causes hissing when accelerating?
Hissing when accelerating If you hear the hissing noise increase as you accelerate the car, the source might be your cooling system. You could also have a problem with a vacuum leak, which means a vacuum line is damaged.
What does a failing radiator fan sound like?
Whirring Noises When the radiator cooling fan motor begins to fail, it can emit a whirring sound or loud clicking. These sounds can also occur if one of the fan blades becomes damaged and starts touching other components. If you are hearing sounds, at least you know the fan is still working, even minimally.
Why does my car make a humming noise when parked?
If your car makes a humming noise, it could mean the differential needs lubricant, the transmission is failing or the universal joints or wheel bearings are wearing out.
How can you tell if your radiator fan is bad?
- Engine Overheating. When the radiator fan isn’t functioning properly, it is not able to adequately cool down the car’s engine.
- Air Conditioner Function Diminished.
- Loud Noise Coming From Radiator Fan.
Why does my engine sound like its hissing?
Hissing. A hissing noise coming from under the hood is generally the sign of a leak, typically in either the cooling system or the vacuum system. If you hear the hissing sound right after you turn off the car, it is often a sign that oil or coolant is leaking onto the exhaust manifold or another heated engine part.
Why does my car sound like a lawn mower?
If your car sounds like a lawnmower, it is likely that you have a leak somewhere in your exhaust system. An exhaust system leak could come from a many different areas in your Kia. There are several parts including gaskets, pipes, hoses, catalytic converters, or the manifold that could need to be repaired or replaced.
Why is my car making a high pitched whistling noise?
A high-pitched, shrill whistle can really get annoying, especially if it occurs frequently while you drive. There are generally two possible explanations for the whistle. The first is that your vehicle is running low on transmission fluid. The second is that your car’s fuel injectors have gotten too dirty.
How do you test a radiator fan?

What happens when a cooling fan goes bad?
If the cooling fan motor fails, the blades don’t spin and they don’t generate air flow. At that point, the engine temperature continues to climb until your engine overheats. Once your engine overheats, you get other warning lights to come on indicating the problem.