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Q: Humming/vacuum sound from engine

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Didn't hear it on the way to work got in car after work and even in park there is a humming/vacuum noise when idling in park and when accelerating and decelerating I think front right to center of engine... tends to quiet down once car is warmed up but still makes the sound... any ideas?

My car has 85000 miles.
My car has an automatic transmission.

Based on your description, it sounds like you might have a vacuum leak. I would recommend looking around under your hood to see if any hoses are flat, torn, or have holes in them. This will create a vacuum leak if any of these exist. If you can not tell if any vacuum leaks exist visually, I would recommend having a qualified professional run a vacuum test on your vehicle and compare the readings to the manufacturer’s specifications. Most vehicles should have around 20 inches of mercury for the vacuum reading. If your vehicle has below 20 in Hg, it is very likely that you have a vacuum leak. If you still cannot find the leak at this point, I would recommend having a smoke test performed. This will introduce smoke into the engine while it is not running and the smoke will escape wherever the vacuum leak is located.

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