I had the exact same noise in my Honda Ridgeline. It is very faint and only happens at very light throttle and while under a very light load. If I increase the throttle or let off of it, it goes away. It sounds like a vaccuum sound. When I had the ridgeline I talked to my techs and they all said it was a common complaint but it was normal. Is it normal in the RL as well?

 

This happens on roads where you are basically coasting around 35-40 mph and just barely touching the throttle.

 

It can also happen on the highway in the same situation. Very light throttle and under a very light load. I don't believe this is a tranny or drive shaft issue. It sounds like a vacuum leak but it might be a normal trait. Like it was on the ridgeline.

 

Maybe I should start by cleaning the throttle body??? I found a few threads on Google about that being a possible cause. Easy enough to do so I will give it a shot tomorrow.

 

Whistling. 35-40mph. Sounds like prop shaft bearing to me.

 

The noise I am hearing I am almost positive is a vacuum or intake type noise. My ridgeline had the same noise since it was new. I got use to it and just ignored it. I might do the same with the RL. I guess it could be the drive shaft bearing issue but I doubt it. The noise goes away as soon as I apply more than very light throttle or let off the throttle completely.

 

Does the prop shaft bearing issue only happen under very light throttle while under a very light load? Most threads I've read about it seemed to show it happened while under heavy load while accelerating.

 

Light or heavy. That 35-40mph range is really the key. Does the sound go away after driving for 5-10 minutes?

 

No. The sound is consistent regardless of time of driving. Just need to be driving under a light load and partial throttle. I mentioned the 35-40 mph range because that is the speed limit on a long road I live off of. The noise is there regardless of actually speed. Just be cruising at partial throttle under light load.

 

Acura released a TSB on this, but I can't find the specific link. IIRC, there is a small knob in the middle of the head unit just above the joystick. Press this nob and turn clockwise until the upper LCD screen says 15 or more. If the problem persists, increase this number until the problem goes away.

 

Lol.

 

Too funny!

 

I have the exact same noise started a few days ago. Its like a supercharger or turbo whine. It happens from slightly above the idle speed to around 2500 rmp with or without load, city driving and when parked. It sound like a vacuum leak. I'll report back after showing it to my mechanic.

 

The noise I have extremely minor. It sounds almost like a vacuum leak. It could be gear whine from the transmission. Since the issue goes away as soon as there is a load that is a possibility. I am almost positive my issue isn't the property shaft because the threads I've read about that issue don't sound like mine.

 

Read up on the RL torque converter issues. Not extremely common, but we have seen them here before.

 

My mechanic thinks the sound is coming from the alternator. So we checked the charging system and ya alternator it is.
Tested at 13.93V without load and 12.35V on load. How long before this leaves me stalled on the road ? I have a 4 months old Interstate MTP battery. I leaving for a 2000km road trip very very soon.

 

My noise is not an alternator but thanks for letting us know. That could help the next person that stumbles upon this thread.

If your alternator is bad I would replace it asap. The RL has been known for being very buggy when the battery or alternator aren't producing enough power

 

Sounds similar to what we heard shortly before our alternator tanked. At first I thought maybe it sounded like a loose belt or something. I'm just very grateful that it waited until we finished our 2000+ mile trip. The alternator died on the very next trip we made out to the store. We first noticed the sound at 2:00 a.m. driving through a scattered fog in a very rural area on the final leg of our trip.

 

So I changed the alternator. Tested the charging system, everything checks out good. 14.09V on load. The whining noise is gone. The car was parked for a few hours, I took it for a ride to gas station. After filling up, I parked in front of their white wall to adjust my headlight beam levels, leaving the car running. I get back in the car and as soon as I pull the shifter in reverse, the "chk emissions, chk transmission" warning came back on. Upon revving, I hear a bearing noise but not as loud or as high pitch as before. FML.