Skip the auto shop - Our mechanics make house calls

Q: Hissing sound

asked by on

Previous Question(Answered):

Q: Hissing sound asked by Jimmy F on August 23, 2016

Hello, on my two cars Hyundai i10 2010 and BMW x3 2006 I can hear a hissing sound when I open the throttle On the Hyundai it can be heard on low RPMs and it sounds like a vanos valve(which I doubt that car has) but on the X3 it is much higher and can be heard at high RPMs (Full throttle).

Follow Up Info: No check engine light on yet at full throttle a burn odor can be smelled. Are these two things correlated?

My car has an automatic transmission.

Hello.

Hissing noises when the throttle is opened can be considered normal. If the hissing noise is excessively loud, or can be heard when the throttle is closed then that may be a sign of another issue, perhaps a vacuum leak. A burning smell can be caused by a few things, commonly by oil or power steering fluid leaks that make contact with the exhaust manifolds. I would recommend having the vehicle inspected by a certified mechanic, like one from YourMechanic, for any leaks, and checked for the hissing sound, to see if it is normal or perhaps related to the issue.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Engine whines, knocks, and has slow acceleration

Hey there. I would suggest you have a mechanic come and listen to the noise and verify the noise you hear. The engine may be making normal noises. You may be hearing the idle control and air pump noises that...

Q: Car misfires after new spark plugs and multiple replacements

Hey there, thanks for writing in about your 1987 Pontiac Fiero. I have the 2.8L engine in my '87 Cavalier Z24 and I know it well. I'm guessing your Fiero has the same engine. One of the best ways to...

Q: My car wont start

Hello. If your diesel engine stopped running in extremely cold weather, then I would check the glow plugs. If the glow plugs are bad, the motor will have trouble starting, especially in cold weather. In regards to your brake system...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.