Q: Can't Figure Out Engine Noise

asked by on October 25, 2016

Hi there! For the past 6-8 months, I've noticed that my car sounds like it's working really hard to do the things it used to do with ease. I have no difficulty or delay in starting the vehicle, but once it's on, there's a loud, low-pitched roar/grumble/growl type of sound, coming from the alternator area under the hood. It happens when I start the car, the car is idling, and especially when I am accelerating. No noise on braking, turning, or coasting. There is no vibration or funny smells. I drive this car about 150 miles every day, to and from school. I have had transmission fluid & filter replacement and flush recently, I use fuel injector cleaner every 3,000 miles, I have the oil changed every 2 months exactly, my battery appears to be in good shape, I just got new tires, and I've never been in a collision in this car. Shocks and struts have been replaced before so they shouldn't be worn, water pump was replaced recently, and all fluid levels are maintained carefully. I'm lost!

My car has 112000 miles.
My car has an automatic transmission.

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