Humming Yaris

[Phaeton]

Mine has the same exact noise, same circumstances.

[mhkritzinger]

hey...

so could anyone find out something about the noise?

[Lafiro]

I still can't figure it out.

So I do not have any real means to get this checked out anymore.

[mhkritzinger]

man thats bad! my dealer told me that when the car is doing it ishould take it in to them but do you think i can get my car to make the noise when i get to the dealer?

Hope you guys can find something!

[Lafiro]

You must tell them to have a tech outside ready for your arrival to hear it before it goes away and testing becomes useless because your not leaving your car their overnight for another tech to abuse it without knowing what the problem is to begin with.

It has been colder these past few days, and on top of that i changed my serpentine belt, and yet, the noise is there, just no where near as loud.

Which makes me wonder if its one of the bottom two pulleys? Since now we can all agree the noise is dominant from under the car somewhere in the vacinity of the engine bay.

[Shroomster]

I'm going to throw out everything I can think of:

I'm leaning towards a rubber part or a stationary part....something not quite tight or fitted against another part properly


mainly plastic pieces like splash guards that can create a harmonic vibration...


but as to the fact that it gains in noise with acceleration I would think it'd be harmonic balancer on the crankshaft but thats a long shot way long shot.


It could be auto transmission clutches/bands that have worn and cause a slightly less than perfect operation during hot temps (seeing as it goes away when in neutral, correct?)

it could be engine tolerances are slightly out of spec (another very far shot)

thats all i can think of currently

[Lafiro]

From everyone who is having this noise;

Maybe it has something to do with the tranny, under strain, and low RPM's?

When is the last time anyone with this problem changed out their tranny oil?

Im on 54k miles, and still haven't changed it. I did post the question though in another thread, so I can try this and post my findings as soon as I can.

[craigq]

Originally Posted by Lafiro

From everyone who is having this noise;

Maybe it has something to do with the tranny, under strain, and low RPM's?

When is the last time anyone with this problem changed out their tranny oil?

Im on 54k miles, and still haven't changed it. I did post the question though in another thread, so I can try this and post my findings as soon as I can.

FWIW I've done about 3 or 4 small-quantity/partial transmission fluid changes (using a 2.5L Pela vacuum pump). Shift quality seems the same since new, the noise was present for a while before the last fluid change and didn't go away after swapping out the fluid. I'll try to pay attention next time it makes the noise...

[mhkritzinger]

hey guys! I have caight my car doing the noise so i recorded it with my phone! ginna take to the dealer sometime next week and see what they have to say! will keep you posted! Have anyone figured something out yet?

[Lafiro]

Nope. Been sick, and its cold/moist or raining outside, so I haven't been able to check.

Please make sure they hear the noise while on a lift, because its from under the car somewhere MOST likely.

[N9QGS]

Okay I'm on the right topic, I agree its rpm possibly related cause the humming will stop if you move the wheel enough etc, I too originally thought it was power steering, but im like their is no pump, then when i heard it between certain shifts, I said well that I think ruled out steering, then I thought transmission, but mine started about 100,000, my tranny fluid has been changed on 2 occasions, and no it did not start after a change, but I will flush and refull my fluid this weekend, and see if it changes. I may try to get a recording of it tonight if it will do it. it does it enough that I think I can capture it with my zoom H2

[N9QGS]

Okay here is the sound: http://public.me.com/n9qgs go under Toyota Yaris and listen to hum.mp3

[Lafiro]

I also hear it when I am coming to a stop, probably from 8mph to 3mph, I hear it, then it goes away once I stop, then it comes back, and goes away, its annoying.

[N9QGS]

Lafiro,

Yours sounds like something related to a belt, it sound svery different then what Im calling a hum. Have you listened to my audio?

[N9QGS]

I re listened t my audio recording over normal speakers it was a little harder to hear, if you have the ability to listen through headphone you will hear it better I think, its a steadily rising hum or tone.

[mhkritzinger]

hey guys.. just wanna know if anyone figured something out yet?

[Lafiro]

Nope, I tried again today, no luck. Got another vibrational noise, noticed the airbox is loose and vibrating a lot with the engine and making contact with the car.

This is all becoming annoying :(

[Bob@MorganBingham.Com]

I also have a humming Yaris Sedan 2010 with automatic transmission. It has made an intermittent sound since the first week I had it. This was upon braking at a stoplight. I could stop this sound by shifting into neutral.
At 18,000 miles I took it back to Frontier Toyota in Valencia, California as the sound was louder.
Two techs heard the sound (I have it on Toyota letterhead). One of them in my presence on a test ride. He also thought it was making this sound while we were driving down the roadway. I have since noticed this can occur but is harder to hear while the car is in motion. He had never heard this type of sound before and it was coming from the "transmission side of the car." After a further check he kindly told me the automatic transmission had been "way overfilled." Good work factory guys.
The brake assist was replaced under warranty at a cost to Toyota of $800.
Sound persisted.
A THIRD tech heard it in my presence on a test ride. A humming sound upon stopping that a slight movement of the steering wheel can affect. He stopped the sound by placing the automatic transmission into neutral as I had been explaining. He said to the Service Manager that "This case needs to be reopened" and that he guessed to to possibly be an "ABS actuator", but not a safety issue.
The dealer kept this car three days afterwards. When I called to check - the gal on the phone said there was no paperwork. When the service manager said to come in - he walked me to the cashier and said there was "no paperwork" and to just call the car up. I received no paperwork as to what they were trying to do or any further repairs made.
The service manager said Toyota did not want to keep replacing parts on an intermittent sound. He advised me to keep driving it until the sound became more persistant and the warranty for such a thing was in the 40,000 mile range.
The sound still occasionally occurs.