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Q: Faint pulsating sound during idle

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After starting my vehicle and driving for less than 5 minutes, I heard my car making very faint pulsating noises at stop lights. A friend suggested that it may be because the heater was on. Is this anything serious?

If the noise you are hearing is coming from the dash area then you may be hearing the blend door electronic actuator controlling the temperature output to the vents. Try to turn off your a/c or heater controls and see if the noise goes away. If it does then this is the noise you are hearing and may be normal. If the noise is clicking or thumping noise then a problem is indicated with the actuator and would need further diagnosis or replacement. If the noise is coming from the engine compartment from the engine, then you may have a problem with the variable valve timing solenoids. The manufacturer just came out with a new technical bulletin for replacing the parts but the parts may not be ready till after Feb. 2016 or later. I would suggest you have a mechanic, like one from YourMechanic, inspect the noise for you to determine if it needs to be addressed and repaired or if this is a normal noise of a component.

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