Q: My check engine light just turned on mid drive and I began noticing a high pitch hum only while accelerating...possible issues?

asked by on

The car drives fine no real stand out issues other than the faint hum. Does not do while in park or in low gears. Starts just as I shift into last gear around 3rpm and 45mph. Sound gets higher in pitch the faster I go making it less noticeable.

My car has 127000 miles.
My car has an automatic transmission.

Hello, There are a number of possible causes for creating a humming sound as you describe, however the most common that would also be correlated to RPM change would the a failing alternator. When the alternator is not working properly, this may result in the battery quickly losing charge and the car losing all power as you have described. You may also notice a whining sound as a result of the bearings inside the alternator begin to fail. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your charging system.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. My check engine light just turned on mid drive and I began noticing a high pitch hum only while accelerating...possible issues?

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: Car always starts but sometimes won't stay running

Claimed by Jeff Engstrom

Q: Hyndai elantra P2196 P2096

Hi there. Typically these codes are caused by an exhaust leak, clogged injectors, or intake vacuum leak. If problems just happened to start after getting fuel, then you may have a purge valve leaking excessive fumes into the intake when...

Q: Q: Transmission "popping" out of gear

This may suggest failing transmission synchros. As you may know, when a clutch drags, it is not letting go of the disk fully which overloads the synchros and burns up the friction surfaces quickly. Synchros work by speeding up or...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
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...