New car brakes sound like jackhammer (no ABS)

Just got my new 2003 Toyota Echo from the dealer tonight. Woo hoo!

Problem is that when I’m waiting at a red light with the car in Drive and holding down the brakes, they sound like a jackhammer!

What the heck is this? Are they defective? The sound disappears when I move the gear into Park.

For the record, I do not have ABS.

That’s very odd. (Note: What follows is mostly guesswork). It may well be that the sound you’re hearing is not coming from the brakes themselves, but from some other part of the engine that is active at low velocities when the engine is in drive but not park. But if you’re sure that it’s definitely related to the brakes, it may have something to do with inadequate brake fluid or a faulty spring. Maybe the brakes are clamping and releasing, clamping and releasing very rapidly. In which case it’s pretty dangerous to be driving that car.

I thoroughly recommend you go back to the dealer and have a stern talk with somebody.

You probably should have turned it right around and brought it back the second it made that noise. At any rate, I agree with Sundance, get that thing back ASAP, no car should make any kind of loud noise while sitting at a light.

I don’t really know what’s causing it, but it doesn’t sound good. I’d try and get them to swap you a new car, if they have one. Good luck, keep us up to date.

Yeah, take it back.

Did you test drive that car first?

Hi all. Thanks for the replies.

Here is an update:

  • The dealer garage is closed today (Saturday) so I can’t take in it today

  • The jackhammer sound only happens intermitanly

  • It happens with the brake pressed down while in D, R and even N

  • I opened the hood and has the little woman press down the brake in an attempt to see if the sound was coming from the engine… but, of course, the brakes refused to make that sound while I was standing over the engine (I will attempt this test later and see if I notice anything rattling around in the engine when the jackhammer sound occurs)

  • I don’t think I hear that sound while driving slowly, so I do think it is related to the brakes

  • The brake fluid container is full

Hey… this is my first post!! :slight_smile: Not to second guess you, but you are 100% sure your car is not equipped with ABS?

Well, since it’s a new car and under warranty, this is just a mental exercise. The described symptom does not fit any pattern I’m familiar with.

There’s a difference between a noise that’s IN the brake system and a noise that OCCURS with the brakes on – it could be one and not the other, or it could be both.

My first thought was that it was related to the tension present with the engine under load (in gear) and the car held stationary by the brakes. This would be consistent with the OP description of the noise being present in D but not in P. However, although it could also be consistent with being in R, it would not explain also having the noise in N. In fact, it’s hard to come up with any plausible explanation for a noise that is present in N but not in P, especially if it only occurs with the brakes applied.

My questions are:
Does the noise definitely occur in D, R, & N, but go away in P?
Does it occur in the other forward gears (1, 2, etc.)?
Can you feel it in the brake pedal?
Does it occur with the vehicle held stationary by the parking brake, with foot off the service (pedal) brake?
Does it occur while braking with the vehicle moving, or does it only occur while standing still?
Are you absolutely certain the car does not have ABS?
Is there any feel for where the noise is coming from, e.g. from the area of the wheel(s), from under the hood, front/rear, left/right?

With more info we might have a better shot at figuring out what it might be. With it being intermittent, it’s pretty tempting to think it’s related to an ABS system, which might be disabled in P.

>>In fact, it’s hard to come up with any plausible explanation for a noise that is present in N but not in P, especially if it only occurs with the brakes applied.<<

Vacuume modulator to the trans?

New pads can stick and slip with just the right pressure (extremely slight pressure) while the car moves (just a few inches)

I’m pretty sure it uses a throttle pressure cable rather than a vacuum modulator.

Probably, I have not seen a vac modulator for a long time.

WTH is it?!?!?

Maybe we get an update Monday night.

Possible trans problem???

Boy, do I feel stupid now…
Following the lengthy list of questions from Gary T, I decided to get better intel on the exact problem. Here is what I discovered:

  • There are two “jackhammer” sounds
  • The first is quieter than the second
  • Both sounds make the front seats and hand shifter vibrate (among other things)
  • I don’t think either sound occurs when I’m driving (but it’s hard to tell for sure)
  • Both sounds occur when the foot or hand brake is used
  • Both sounds occur when the car is moving (without touching the accelerator)!!!
    This last bit of info, or course, indicates that the sounds are not related to the brakes but, rather, to the car travelling at very low or no speed.
    I then made another stunning discovery: The louder of the two jackhammer sounds is caused by the hood vibrating!
    (This explains why the louder sound never happend when I was standing over the open hood. Man, I feel dumb…)
    TWO LAST QUESTIONS
    1/ What could be the quieter of the two jackhammer sounds?
    2/ What needs to be adjusted on the hood to fix the rattle?

Sometimes the rubber bumpers that the hood rests on when closed make noise as the hood moves on the rubber. A dab of lube on the top of the bumpers may quite the hood.

If that little hamster cage for an engine is vibrating enough to rattle the hood, something is definitely wrong with the hood or the engine…

UPDATE:

My dealer inspected the car and said that the vibration of the hood and the other vibration was caused by a loose cruise control wire. They lubed it up and now it’s fine.

This wasn’t explained to me very well, and I intend on speaking to the mechanic later to get exact details.

But, does this make sense to anyone?

Well, maybe it caused the engine to idle funny, and got it vibrating a lot. Engines do idle differently when stopped in D or R vs. P or N. (still doesn’t explain why it happened in N) You could have just hit a resonant frequency at certain times and whammo! jackhammer sounds.

You can probably adjust the rubber stops the hood rest on up or down by turning them. If they’re only resting on there enough to hit while vibrating, you should raise them enough so that the hood always makes contact with them, but not enough to where the hood rests too high in relation to the other body panels. Your mechanic probably already did that though to make sure that once the lube wears off, it won’t start banging again.

Hi friends,

I just took my 1997 Toyota yesterday in for a new front tire and a new starter. My mechanic said I was due for new brakes within the next 5,000 miles or less than six months, but I told him (truthfully), I only drive about 1,200 miles a year. (My car’s odometer is only about 135,000 miles for her age.)

Next thing I know, I’m at McDonalds drive-thru, and there’s a weird jackhammer noise, but only when my car is in Drive and I’m stepping on the brake. When I got her home and put her in Park, NOTHING.

Is this a “holy cow, get new brakes immediately!” situation???

Thanks for any advice.