spring boing at brake pedal?

[AustinCyclist]

Hey, anybody get this? Doesn't appear to be affecting anything, but I've noticed it happend about 10 times now, if I'm hopping a curb, backing up once, or just other weird times, I get a spring release sound.. boing!! under the brake pedal area.. don't know if there is a coil spring that is getting partially caught on a lip and then shaking/condition allows it off the lip for a sudden expansion that I'm hearing. what would the spring be part of, brake or gas pedal? It feels like its under the floor of my feet, can feel the reverb.

Also get it with sudden accelerations into traffic coming from a side street.. if I really floor it (ie. chassis is probably getting tweaked enough to bump the spring, or whatever is caught, off the lip)

 

[rickwol]

Hmm. I think I've heard the sound you are experiencing a couple of times and not just with this vehicle so assume it to be normal. I always thought it might have something to do with the ABS. However, I don't ever recall hearing that on acceleration. With me, it's usually heard if I hit a pothole in the road.

 

[offroadingatc]

Hey, anybody get this? Doesn't appear to be affecting anything, but I've noticed it happend about 10 times now, if I'm hopping a curb, backing up once, or just other weird times, I get a spring release sound.. boing!! under the brake pedal area.. don't know if there is a coil spring that is getting partially caught on a lip and then shaking/condition allows it off the lip for a sudden expansion that I'm hearing. what would the spring be part of, brake or gas pedal? It feels like its under the floor of my feet, can feel the reverb.

Also get it with sudden accelerations into traffic coming from a side street.. if I really floor it (ie. chassis is probably getting tweaked enough to bump the spring, or whatever is caught, off the lip)

I have this happen about once a month in the same situations as you, except I've never had it happen when accelerating.

 

[ClockWork]

I doubt its actually what you described it to be.

My 4Runner and Cruiser do the exact same thing occasionally.

 

[AustinCyclist]

I have this happen about once a month in the same situations as you, except I've never had it happen when accelerating.

its when accelerating out of a corner, borderline fishtailing the vehicle.. so another cause... maybe some type of traction control applying brake to a specific wheel in which makes the sound/reverb? I don't recall hearing it from a straight line acceleration.

although, as mentioned, I also have had this occur couple times when a traction control mechanism wouldn't be kicking in, slow/normal conditions. Such as backing it up.

 

[FlyNavy]

its when accelerating out of a corner, borderline fishtailing the vehicle.. so another cause... maybe some type of traction control applying brake to a specific wheel in which makes the sound/reverb? I don't recall hearing it from a straight line acceleration.

although, as mentioned, I also have had this occur couple times when a traction control mechanism wouldn't be kicking in, slow/normal conditions. Such as backing it up.

It's the traction control doing its thing, coming off the gas and applying the brakes as it senses wheel slip. Normal as far as I know.

When backing up you probably shifted into drive with the car still rolling backwards a little, triggering the hill hold function.

 

[rickwol]

It's the traction control doing its thing, coming off the gas and applying the brakes as it senses wheel slip. Normal as far as I know.

When backing up you probably shifted into drive with the car still rolling backwards a little, triggering the hill hold function.

I'm pretty sure I've experienced and heard this sound on vehicles without traction control. Not to say that's not what it is with the T4R.

 

[offroadingatc]

I'm not convinced its TC, I'm pretty well acquainted with that and it seems to occur in situation where TC shouldn't be a factor. Not a mechanic or expert though, so grain of salt.

TC light does come on when that sound occurs, so that would seem to indicate that it is involved.