I've noticed a strange humming noise almost a "whir" when I'm accelerating between 30-40 mph. I've only noticed it in the morning.

Has anyone else experienced this?

 

I have...noticed it today when driving @ 60-70 mph. Have you found a solution?

 

I notice it in the morning or in case of driving after a long stoppage (hours).
It may be some kind of oil pump or something. It does sound like it is part of the design and not something breaking down.

 

I am not a mechanic by any means and I may be soooooo off that people will think I am nuts but in the TL, the same description has been described as the "propeller shaft" and was somewhat common. Does the RDX have a similar device?

 

Propeller shaft = drive shaft. Yes, the add models have a drive shaft.

 

I hear more of a whirring noise when lifting off the throttle and coasting, it only lasts 3-5 seconds

 

Just got RDX AWD w Tech and heard the same "whirring" (sounds more like something spooling up) sound. It appeared to be more pronounced soon after starting than as the car warmed up. But it would be useful to understand what it is.

 

I just got off the phone with the service department and I can't say for sure if everyone has the same symptom but in my case the shudder / rumble was confirmed by the tech working on it and it's the VCM (Variable Cylinder Management). Basically when you're cruising at low RPM's (1000-1200 approximately) but sufficient speed to justify the transmission putting you in to 5th or 6th gear (in my case 40mph or so) the engine will hesitate or shuddle momentarily, similiar to right off the line on a rolling stop as it determines how many Cylinders to fire.

The service department called Acura factory and confirmed that this is an intended effect of VCM. They wiped my data map history with the hope that it will temporarily avoid overshifting up at such low rpms. Once I drive it a bit I will follow up.

 

I hear the same "whirring" sound at idle, cold or hot. But I can also duplicate the noise by turning the ignition to "on", but it only lasts about 3 or 4 seconds. With the engine running, it's constant. Any guesses?

 

My guess is that what you are hearing is the electric fuel pump. It would be on all the time while the engine is running. When you turn on the ignition but do not start the car it would pump until it makes the proper pressure and then stop since the engine is not using the fuel.

 

I know this is old but was just wondering if anyone ever found a good solution to this. I own a 2005 Acura RL and while im driving under 30mph its normal as soon as I hit 30 I get a humming noise wich sounds to me like its coming from the passenger side of the dash board. once I hit 40mph it goes away.

 

I hear the same noise with my '13 RDX, especially when coasting at 30-40 MPH. Just had mine in for service and the '14 RDX loaner made to same noise. Doesn't sound like an issue to me, just something with the design.

 

I have a 2015 RDX and I heard this whirring sound after driving it the first 100 miles. In my car, it was very noticable under a steady cruising speed of 35-37 MPH.

I brought it to my dealer, they diagnosed it as the rear propeller shaft bearing. The bearing is an intergral part of the shaft, so they replaced the entire shaft/bearing assembly.

I then drove the car home, drove it to work and....the whirring sound came right back. The car is currently back at the dealer today. They are telling me they will get to the bottom of the issue and they are working with Acura engineering (o.k. great).

I have read that there is a quality issue with these prop shaft/bearing assemblies at the manufacturer/source. I won't be surprised if they once again replace the replacement assembly they installed as it probably also has a bearing flaw. I told them to keep the car until they solve the problem.

If they get to the bottom of the issue successfully, I'll report back with the solution!

BTW, the 2015 RDX loaner I am presently driving doesn't make the same sound.

 

I have a 2015 RDX and I heard this whirring sound after driving it the first 100 miles. In my car, it was very noticable under a steady cruising speed of 35-37 MPH.

The dealer has given me a loaner and is all-over the issue, thankfully, and they now have the o.k. from Acura to replace the transmission. Let's hope that nips it in the bud because they had already replaced the propshaft, rotated the tires, and eliminated the chance that it could be coming from the propshaft transfer case.

I don't know about other owners, but to be blunt, I can't pay high 30's for any new car that I drive around town in this speed range all the time and have to drowned-out the sound with the radio whilst it constantly makes a driveline sound like a washing machine spinning a load at 500 rpm.

 

i know this is like a year old, but has anyone found out the issue ?

 

I know that I'm 9 years behind but have you find out what the issue was?
Mine is the same exact thing that you are describing. I have a 2008 RL Base

 

I know that I'm 9 years behind but have you find out what the issue was?
Mine is the same exact thing that you are describing. I have a 2008 RL Base