Also experiencing excessive noise, 70 mph to 75 mph.

Your post peaked my interest. We have a 2008 Sienna with 7k miles, the car has been perfact other than oddly highly engine noise at certain speeds. My wife hasn't noticed it at all. I have noticed three times in the past few weeks, it occured at 70mph to 75 mph. Decreasing or increasing speed quieted the noise immediately, my thought was a poorly designed exhaust system. Not sure how to say it, but I would call it harmonic distortion. The engine and drivetrain feel normal, the noise level just gets loud. Like you, I have never experienced this with any vehicle. I am planning to take it in for evaluation, our issue seems to be intermittant so I want to create a case history. Good luck, please keep posting your progress - I'll do the same.

 

2006 sienna

same here, check your van next time, mine makes the noise at 2500 rpm, the loudest when going up the hill. Mechanic and the salesman said they would not want a car like that. The Toyota replied to reset the computer. That did nothing. Don't know what to do, waiting for Toyota to fix it for almost a year. I want to get rid of it - first and last Toyota for me.:disappoin
Jacek.

 

2007 Sienna vibration

I have a 2007 Sienna with a vibration @ 2300 rpm. Every time the engine goes through that rpm under load the vibration occurs. The noise sounds like a harmonic resonance "buzz" as if a shield or guard of some sort resonates at that frequency. Local dealer verifies that it is there but they say they can't duplicate on the lift where they could check for vibration. I find the buzz very annoying and not what I would expect on a Toyota! I am glad to hear that the problem exists elsewhere so there might be hope of finding a fix. I have not done any investigation other than listening to see if I can isolate the sound to one area. But it seems that the engine needs to be under load for it to happen.


If anyone finds the cause I would appreciate having it posted to this site so we can all drive in peace!!


Otherwise the Sienna is a very refined vehicle, comfortable and easy to drive.

"Every task is simple if I don't have to do it".

 

I have a 2008 Sienna with exactly the same noise. I actually thought it was getting better after 1500 miles, but my latest trip proved my wrong. Not sure if I'd called it a buzz or a growl, but its annoying as hell

 

Now its happening in the Camry

I recently bought a 2009 Camry (Manual Transmission) - and i get the same annoying noise at 2500 RPM - doesnt go until I hit 3000!!!! Extremely annoying since its a low hum and thats the speeds and RPM you stay put on the Interstates! The dealership had no idea what to correct - since its technical not a mechanical fault. Taking the issue with Toyota tomorrow but doesnt seem like folks on this forum had much luck!!

 

Now its happening in the Camry

I recently bought a 2009 Camry (Manual Transmission) - and i get the same annoying noise at 2500 RPM - doesnt go until I hit 3000!!!! Extremely annoying since its a low hum and thats the speeds and RPM you stay put on the Interstates! The dealership had no idea what to correct - since its technical not a mechanical fault. Taking the issue with Toyota tomorrow but doesnt seem like folks on this forum had much luck!!

Were you able to figure out the cause. I have the exact same issue at the rpms you mentioned

 

Does that Camry have the 3.5L engine too?

 

Nope its normal 2.4 L Engine.

I also came across this post which I thought was quite informative

http://www.darklair.com/monte/exhaust.drone.html

 

I have a 2007 LE that does not exhibit this condition. It currently has 40K mi on it and the only things I have done to it are added some sound dampening material to the doors and to the rear of the van to reduce the boomieness of the stereo . I also have added a hefty Stainless steel exhaust tip to the end of the tail pipe. I bought the van used with 36K on it and while I cant say that the mods have changed anything, I just know that my van does not seem to have this problem. I have read on other forums that other people do have this problem.

 

I think I got it.....

I was poking around under the van looking for a loose heat shield that might be causing that annoying resonance at 2500 rpm. Everything was tight, but out of frustration I grabbed hold of the exhaust system and moved it side to side. To my surprise, now my resonance is gone.

I can only imagine I repositioned the spring-loaded exhaust coupling a little. So far so good, but I hope this doesn't become part of my weekly maintenance routine.

 

07 Sienna Exhaust Drone Sounds

I too have a problem with a drone sound from what sounds like the exhaust. I have a 2007 LE with the towing package. My first assumption was a problem with the transmission. My problem seemed to be intermittent but after driving with my wife driving it she was able to consistently reproduce the sound. As we accellerate form 0-50 we get the hum or drone at a constant volume until the car reaches 50mi/hr. It seems that the transmission shifts and then all is quite until you get below 50 at which it seems to come back.

Now that I know others are having this too I may have to track RPMs and the noise to be sure if it is RPM related instead of gear related. From the posts it doesn't sound like it is a problem but more of an annoyance. I also have an 07 Avalon and did expect the Sienna to be quiter than it is since we planned to take long trips in it. This sound might make it difficult to hear music or listen to a DVD if it comes back at 70-75mi/hr.

 

lets get LOUD

Just got call from Toyota with solution:
do not drive at 2500 rpm!! :headbang:

Decided to file a dispute thru CAMVAP. Week later Toyota called - they would like to send a tech to check it. replacing some support studs, adding weight to the exhaust and changing the front pipe did not fix it but made it worse at 1500 - 1800 rpm.
Waited 1 1/2 month -no one called to check if this improved the situation. Called Toyota to report that - someone called today with above solution. The lady even told me that she has the same vehicle and the noise does not bother her. According to TOYOTA this is normal behaviour of the vehicle.

waiting for response from CAMVAP - Toyota did not contact them since they ask Toyota for explanation.

No matter what happens, even if CAMVAP orders Toyota to buy back the van I will loose some $$$.

 

Droning sound

The sound you are hearing is a harmonic oscillation caused by a variety of factors. All metal boxes with wheels (aka=vans) have a frequency tuning range. Accelerate to that mysterious frequency and your vehicle will resonate with a specific tone. It can be antennuated by adjusting the exhaust system, e.g. moving, wiggling, etc.

My '05 Sienna (3.3L) has the same phenomena at 50-55mph, especially while leisurely accelerating to freeway speeds. One could call it a design flaw or error. In truth, all moving vehicles and reciprocating engines have frequencies. Diesel engines have deep, low frequency hum while the Sienna has a variable range of frequencies, exacerbated by tire-tread design, pavement construction, wind currents, etc.

I'm in my fourth year of ownership and it's a little annoying but I found the same reality two weeks ago in my wife's '08 Ford Escape. In desert cross winds in the mountains east of San Diego, the Escape let loose with a high-pitched whine that was very annoying. Once we moved down the pass to where the winds were different, the whine went away. The wind had created a harmonic with the frequency of the Escape that produced a crazy sound.

Best wishes!

 

It's Fixed!!!!!

The Toyota service tech "adjusted" the rear exhaust manifold heat shield and the annoying noise around 2500 rpm is gone. Furthermore I think the engine is quieter overall. Its like a getting a new car all over again.

The tech said he "had a hunch" about that heat shield, but upon inspection it didn't seem loose at all. He decided to "adjust" it anyway. I use the term "adjust" since the tech said there were no bolts or screws to tighten. It sounds like its crimped on somehow.

 

Its been a few weeks now and still no annoying resonance. That exhaust heat shield must have been it.

 

Bill, glad to hear that your van is still quiet.:thumbsup: My experience with heat shields on other vehicles has been similar (IE: buzzing at certain engine RPM's). Once the heat shields were removed, the noise went away.

 

Now I have a new problem....

I noticed a drone (resonance) at 2000 rpm that is evident during acceleration and at criusing speeds (70 mph). This time I focused on the air intake. I found that disabling the aux air intake elimininated the drone. That's fine for a test, but I don't think I want to run it that way all the time. I plan to attach a vacuum gauge to the valve and monitor the operation of the valve under various rpm and load conditions.

Has anyone else experienced a drone at 2000 rpm associated with the aux air intake?

Does anyone know what conditions trigger the aux air intake valve to open? I assume its some combination of engine rpm, engine load and vehicle speed.

 

Thanks to the people of this forum. I learned a lot from here.

I owned a Toyota Sienna 2005 XLE limited and I had the same noise when accelerating. I took it to a honest mechanic shop and he showed me that the gasket is finished and need to replaced with a flex pipe. Took him 10 mins to fix while I was on the phone and wallah car is running like New.

If you need my help email me Masood.ali1974 at gmail. I will explain you better