GR Yaris (Gen 2) have a noise on my gen2 motor?
- Thread starter JFO
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tonic
Totally Hooked
- Aug 31, 2023
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I can't answer your question definitively, but I can suggest some ideas that might help you investigate that noise if you decide to pursue it.
Your RPM ranges roughly from 1800 to 2400 in 3rd gear, which is 30-40 revolutions per second (or Hz). This is the speed of the crankshaft, but we usually can't hear it directly as it quietly slides on the oil film.
What we can hear are the exhaust pulses exiting the tailpipe. Since the GRY has three cylinders, at 2400 RPM it "puffs" 3600 times per minute, or 60 times per second - 60 Hz (2400 / 2 * 3 = 3600; 3600 / 60 = 60). Additionally, the closing of the intake and exhaust valves generates noise. As both pairs of valves open and close during each combustion cycle for every cylinder, their frequency is twice that of the firing rate - 120 Hz at 2400 RPM.
The noise you're referring to seems to be approximately 340-350 Hz, which is about 10 times per engine revolution. If I had to guess, it might be related to small gears (e.g. a 10-tooth gear) inside the gearbox. At the 18-19 second mark, when you slightly lift off the throttle, the noise becomes quieter. This could be due to the gear teeth unloading.
However, all of this is just speculation. Dealers often use multi-microphone arrays to attach to various parts of the car to locate the source of a noise. If it really bothers you, you could explore that route, but it may be excessive.
Just drive your car and let the parts settle in, it will get quieter
Sound spectrogram of your recording. x - time, y - frequency, colour - sound level.
Your RPM ranges roughly from 1800 to 2400 in 3rd gear, which is 30-40 revolutions per second (or Hz). This is the speed of the crankshaft, but we usually can't hear it directly as it quietly slides on the oil film.
What we can hear are the exhaust pulses exiting the tailpipe. Since the GRY has three cylinders, at 2400 RPM it "puffs" 3600 times per minute, or 60 times per second - 60 Hz (2400 / 2 * 3 = 3600; 3600 / 60 = 60). Additionally, the closing of the intake and exhaust valves generates noise. As both pairs of valves open and close during each combustion cycle for every cylinder, their frequency is twice that of the firing rate - 120 Hz at 2400 RPM.
The noise you're referring to seems to be approximately 340-350 Hz, which is about 10 times per engine revolution. If I had to guess, it might be related to small gears (e.g. a 10-tooth gear) inside the gearbox. At the 18-19 second mark, when you slightly lift off the throttle, the noise becomes quieter. This could be due to the gear teeth unloading.
However, all of this is just speculation. Dealers often use multi-microphone arrays to attach to various parts of the car to locate the source of a noise. If it really bothers you, you could explore that route, but it may be excessive.
Just drive your car and let the parts settle in, it will get quieter
Sound spectrogram of your recording. x - time, y - frequency, colour - sound level.
JFO
New member
- Jan 1, 2025
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Amazing, your analysis is incredible, thank you so much!
I showed the car to my auto mechanic, but for now, he has no idea and is still investigating. He plans to contact Toyota. I’m not sure if this changes anything about your analysis, but here’s some additional information:
why is the noise not always present with the same rpm?
I’ve uploaded another video about the same issue.
I showed the car to my auto mechanic, but for now, he has no idea and is still investigating. He plans to contact Toyota. I’m not sure if this changes anything about your analysis, but here’s some additional information:
- The noise occurs at any low speed, even during gear changes.
- It seems the noise is much easier to trigger and perceive when the car is cold, below 5°C.
- The noise is only noticeable between 1800 RPM and 2500 RPM, and then it disappears.
why is the noise not always present with the same rpm?
I’ve uploaded another video about the same issue.
Last edited:
It's hard to tell from the video... I don't think I hear it like that. I hear a deeper sound in mine, even when it's cold... when it warms up it almost disappears... and I noticed, like in second gear, if you slow down almost to a stop, you accelerate very little until the clutch engages (at about 25km/h) at the same engine revs, it starts to do it...
For example, I feel it slightly darker (it's difficult to understand from the video if it's the same) and I noticed that it starts to do so at the same engine revs, when the clutches engage... because the gearbox is a torque converter but then it has clutches to better engage everything...I can't answer your question definitively, but I can suggest some ideas that might help you investigate that noise if you decide to pursue it.
Your RPM ranges roughly from 1800 to 2400 in 3rd gear, which is 30-40 revolutions per second (or Hz). This is the speed of the crankshaft, but we usually can't hear it directly as it quietly slides on the oil film.
What we can hear are the exhaust pulses exiting the tailpipe. Since the GRY has three cylinders, at 2400 RPM it "puffs" 3600 times per minute, or 60 times per second - 60 Hz (2400 / 2 * 3 = 3600; 3600 / 60 = 60). Additionally, the closing of the intake and exhaust valves generates noise. As both pairs of valves open and close during each combustion cycle for every cylinder, their frequency is twice that of the firing rate - 120 Hz at 2400 RPM.
The noise you're referring to seems to be approximately 340-350 Hz, which is about 10 times per engine revolution. If I had to guess, it might be related to small gears (e.g. a 10-tooth gear) inside the gearbox. At the 18-19 second mark, when you slightly lift off the throttle, the noise becomes quieter. This could be due to the gear teeth unloading.
However, all of this is just speculation. Dealers often use multi-microphone arrays to attach to various parts of the car to locate the source of a noise. If it really bothers you, you could explore that route, but it may be excessive.
Just drive your car and let the parts settle in, it will get quieter
Sound spectrogram of your recording. x - time, y - frequency, colour - sound level.
View attachment 33344
Well it's noisy car, and makes a lot of strange noises. Mine changes sound to this deeper you mention everytime the clutch engages - and it's mostly noticable in 2nd gear. However this high pitching sound is sometimes also present - even when driving on the autobahn on 7th or 8th gear. And it's not very pleasant noise
My gearbox also does not like to shift down from 3rd to 2nd when cold. It prefers to keep the 3rd even at speeds like 20 km/h. The gearbox engages the torque converter to smooth things out, but it's strange behaviour. It behaves like this since absolutely new. When the oil warms up, things change, and it normally shifts down.
I've noticed that it often adapts, depending on how it's been driven before... depending on that, it stays in third gear or shifts down to second... it depends on the circumstances... I've now said to myself: if it breaks, I'll think about it... but I also get paranoid about noises... for example, in fifth gear at low revs I feel a vibration like something vibrating under the hood or dashboard... maybe the gearbox?!?! I don't knowWell it's noisy car, and makes a lot of strange noises. Mine changes sound to this deeper you mention everytime the clutch engages - and it's mostly noticable in 2nd gear. However this high pitching sound is sometimes also present - even when driving on the autobahn on 7th or 8th gear. And it's not very pleasant noise
My gearbox also does not like to shift down from 3rd to 2nd when cold. It prefers to keep the 3rd even at speeds like 20 km/h. The gearbox engages the torque converter to smooth things out, but it's strange behaviour. It behaves like this since absolutely new. When the oil warms up, things change, and it normally shifts down.
Nah, vibration is normal. My vibrates everytime it locks torque converter / engages the clutch pack. And yes, it's mostly noticable at low revs. What's funny - when driven hard, none of those noises appear. When you push it, it's super snappy and responsive. Maybe that's a solution - not to lurk around, just floor it.
the solution is full gas
Anyway, it's great to see that the gearbox software is designed to go fast... if you want to go in fifth gear at 2000 rpm and move the lever to manual, it will automatically shift to third or fourth and bring the revs to around 3000... I've tried various situations and it shifts down enough gears to take you close to 3000... as if to say: don't go lower
I really like this gearbox. My only complaint is that it should engage the clutch pack on 2nd gear much earlier. I don't like this "rubber band" feeling. Apart from that it's fine - almost as quick as my previous DQ381 on upshifts, noticably quicker on downshifts.the solution is full gas
Anyway, it's great to see that the gearbox software is designed to go fast... if you want to go in fifth gear at 2000 rpm and move the lever to manual, it will automatically shift to third or fourth and bring the revs to around 3000... I've tried various situations and it shifts down enough gears to take you close to 3000... as if to say: don't go lower
when you make a lively start and it does 1-2 the gear change is rubbery, not decisive... this is a shame
Sport mode helps, but it's no good for daily commuting, so I assume I have to live with that. Toyota says that in the MY26 they tweaked the software of the gearbox to reduce upshift times, maybe in some time there will be a possibility to uprgrade ours.
Let's hope they apply it to our "old" cars too. In any case, sport mode is nice even if you're going slowly... I also find it more precise when downshifting... in fact, when the car is warm, even if I'm driving normally, I put it on...
For the time being I did "instrument cluster recall". I don't know if yours is affected, mine was. Obvious symptom was that it couldn't remember tire pressure screen -> everytime I had to manually activate this function in the instrument cluster. With this new cluster software it's not an issue any longer.
Mine also needs to receive that update but my official workshop told me they haven't received anything about it yet…
I'm glad to find out they fixed that bug