Unexplainable, Undiagnoseable, Unlocateable Flapping/Gringing Sound

It's coming from right under my feet. I can feel it in the gas pedal if I'm not on the brakes. Oddly enough I did check the fan blades because that's the kind of sound it's making. But I did not find anything in there rubbing. Also, great thought on the skid plate because for a while I thought for sure that was it. But as it turns out it's not. What's funny is that what he describes, the fan blade hitting a loose wire or something that's pretty close to the way it sounds except for the metallic sound maybe I should say metal on plastic sound. Another poster mentioned the sound something makes when you gem a piece of plastic into bicycle spokes that's also pretty good way of describing it.

 

I notice on my truck when a motorcycle with pipes rides by i can feel the vibrations of it in my gas and brake pedal. I do remember noticing a thread on some fan motors in the glove compartment box going bad in 3rd gen tacos.

https://www.tacomaworld.com/posts/17743240/

 

I have this issue too, I have a 2016 SR5 4x4 DCSB. I only get this issue while leaving my neighborhood, while going down the dip diagonally at a higher speed. I never use my brakes on it, but I hear and feel the exact same thing you are.

The indicator lights come on with ABS activation. It’s hard to miss, so it’s pretty clear that is not it. Also, this occurs when the gas pedal is being pressed, so again, not ABS.

I have seen a few threads on this. The general idea is that it is only SRs and SR5s. Many people have reported the problem resolving when upgrading front suspension, as it was believed to be the hitachi struts. Yours continuing after the lift is interesting. What lift did you install? I would suggest checking out the upper and lower control arms, and the spindle. Look for a rubbing spot, paint rubbing, metal gouging, something like that. This has to be suspension related since it only occurs when going through dips, and it’s only felt from the front moving.

Again, I thought it was the struts, but now I’m thinking it is the upper or lower control arms, or spindle. Maybe the front torsion bar. Something that moves with the front suspension that both 2WD and 4WD modes have.

 

Yeah that is the abs because the traction control system senses slippage and is responding.

 

I was guessing it could be traction control, I know that it uses the ABS system for traction but would you feel that in the gas pedal? I thought it could only be felt in the brake pedal.

 

Yep. It's a strange characteristic of the truck for sure.

 

A bad brake booster with a failed diaphragm also makes wierd noises and vibrations on the pedals.... but its probably not that.

 

My SR has done this since new, every time I take left turn over a particular dip in the pavement.

Sounds like the bad body-mount issue, since you've ruled out the suspension. https://www.tacomaworld.com/threads...at-noise-may-not-be-your-leaf-springs.464993/

 

This evening I crawled under my truck and left it running. There is absolutely nothing under there that is at such close tolerance that it would be rubbing or bbrruupp'ing. Climbed up inside of the hood/ engine compartment, nothing. The hard part about this is, I can go weeks without it repeating the noise. Bumps, dips, potholes, no noise. I will even drive through an area where it has "caused" the bbrruupp bbrruupp sound and it will not duplicate. No matter what, no joy in attempting to duplicate. Then one day out the blue after a few or several weeks of silence- bbrruupp bbrruupp! At like 10-15 mph over the slightest dip. F**cking maddening!......

 

Have you tried recalibrating the VSC?

 

I had the same thing happen to my wife's Honda Odyssey. Same exact symptoms and noise you are referring to. (Metallic burrrr,ing sound) After it drove me nuts trying to figure it out, I took it to a little mom and pops shop when the dealer couldn't figure it out. Turns out that the inside weld on the bottom stock header that connects to the cat was slightly cracked. The noise was most predominant when the car was cold in the morning. Like I said, drove me nuts. I couldn't figure it out because I couldnt see anything that would cause the noise with the car jacked up. Long shot with my old odyssey not being a taco, but give that a consideration. Might be something similar. Good luck!

Fyi, after changing out the bottom section of the cat, the noise went away for good.

 

Shit, come to think of it, I also had a 2006 Yukon and had the similar thing as well. The suv only had about 5k miles on it when the noise started. I was able to get it to do it on the spot by putting the car in drive, stepping on the brake, and giving it a little gas. That for what ever reason made the burrring noise do it on the spot. Took it to the dealership when i figured out how to reproduce it after a couple of "unable to reproduce visits" and when the service advisor heard it, he said "i know what it is"... it was a cracked cat converter heatshield. I'm betting that your problem is something related to a crack somewhere along your exhaust system. That's two for me I guess with similar noise as the problem you are dealing with...

 

I know the sound a cracked exhaust makes, and this sound is nothing like that.

OP, if its the ABS and traction control, how about disabling our traction controls over said bumps that create the sound and seeing if it ever happens again. Could be a while, but we can do it for science. If we disable over those bumps and it doesn’t happen for like a month, we could assume it’s that.

 

I have the same damn problem on my 16 TRD Sport. It drives me crazy and can not figure what the problem is. I tried taking it to the dealer once. The dealer couldn't replicate the sound. They suggested it was items rattling from the backseat compartment.. go figure... Any who, exactly what you are saying is the same problem I am having. I have narrowed the noise down. I am pretty sure mine is coming from the rear right side of the truck. It only happens traveling at slow speeds while making turns.

 

https://www.tacomaworld.com/threads...at-noise-may-not-be-your-leaf-springs.464993/

 

Could be ABS going crazy.

 

Yes, I did have that done. But thanks anyway.

 

I definitely think it's worth trying. I'll turn it off starting tomorrow and everyday for at least a few weeks. In the interim, maybe someone will get lucky and come up with a for sure cause?

 

You know, I'm guessing it could be. One thing for everyone to keep in mind- this is happening really slow speed less than 15 miles an hour. And it is happening in conjunction with the suspension basically bouncing up and down, but it's a very slight up-and-down bounce. The weirdest part is the speed at which the bbbrrruuuppp is occurring... nothing is rotating as fast as the sound that it's making. Like myself and an earlier poster said- take a small, high rpm box fan, change the blade to metal, then jam a sheet metal strip in there. I'm telling you, it's f'n crazy!!!

 

My truck has had two days in the shop there sourcing the squeak in the dash. They are projecting another two days and have already billed toyota Canada for $2400 lol it wasn’t even that bad but just annoying. Thank goodness it’s under warranty!