Hi,
Have a 2007 RDX Tech;
When it is cold , starts up with a howling /whisting sound .
After the Rdx warms up the sound is gone.
Only happens on first start up and the rest of the day is
fine.
Acura dealership could not fine source of sound.
Just that it is on belt side of engine. Possiblely a bearing
in the water pump or alternator. Rdx is not overheating
and electrical circuitry tested fine.
Also is not the power steering pump/o-ring.
Dealership started RDX without serpentine belt and no sound was heard.
Left in the position of could be's. Told wait until it gets worse,
which is not acceptable to me.
All help is appreciated.
Thanking you in advance

 

did they check for an air leak?? also it might be the turbo warming up that you are hearing

 

Said they checked the fuel injector circuitry,vacuum hoses and found
nothing.
Regards

 

How long does it last?


My wife's 08 RDX Tech has a sound at start up that lasts for maybe 2 to 3 seconds that the dealer I used to go to couldn't diagnose it as well. We complained multiple times.


I thought it was a fuel pump but I now actually think it is an air damper switching between fresh and recirculating air. Just this year, we started hearing it when the engine was warm and it coincided with the air conditioner starting and stopping in auto mode. Haven't confirmed but that is my suspicion.