Skip the auto shop - Our mechanics make house calls

Q: Revving and humming noise while driving - 2006 Scion xA

asked by on

Several days ago while driving my car, a revving sound developed. I thought perhaps it was the engine revving, but I noticed that the RPM gauge was normal. Today, the revving/humming noise begins after I’ve been driving about 20 minutes and the sound lasts about 6-8 seconds. It will repeat this by continuing on/off for about 5-6 times and then the sound stops. The car drives well and no problems to report with the starting, accelerating, braking, etc. There are no lights on the dashboard. I took it to a mechanic and he couldn’t find the problem. In your experience, what is causing this revving and humming sound?

A: It sounds like your cooling fan kicking on ...

It sounds like your cooling fan kicking on and off. It’s even louder and more pronounced when the AC is on. The strain on the engine also will cause the RPMs to jump up a little bit during these cycles. If you would like to have this checked, a qualified professional from YourMechanic can come to your car’s location to diagnose the noise and recommend a correction.

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: Vibration coming from wheel and brake pedal when I'm idle

Hey there, thanks for writing in about your 2005 Scion xA. You need to check the brake booster to see if it has a vacuum leak in the check valve or booster when you are pressing on the brakes. If...

Q: 2011 Scion XB ECM replacement cost.

Hi there. The time to replace an ECM (Engine Control Module) on a 2011 Scion xB with a L4-2.4L engine is around 1 to 2 hours not including programming the ECM. ____________________________________________ Billing question was sent to CS for the...

Q: Car vibrating at high speeds

Suspension and steering component wear or damage can cause vibration and noise issues to emanate from the tire area. If the wear or damage is severe enough failure of a component can occur leading to a possible accident if the...

Related articles

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...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...