I've had this noise for a while, I've searched but couldn't find anything similar. The car is an '03 LX/5spd w/60kmi and bone-stock.

Whenever I'm coming to a stop & braking semi-hard, as I'm almost completely stopped and letting off the brakes I hear a loud "POP" from the front end.

If I slow down reaaaaallly gradually, it doesn't do it....but I don't have to be going fast to cause the noise, either. Everything feels/drives nice & tight, and I've pulled/pushed/pried on everything in the suspension while the car is in the air & haven't found anything loose.

I don't really *feel* the noise, just a little bit under my feet, but not in the steering at all. I have a friend w/a Ford ZX2 who had a similar problem/smptoms that ended up being ball joints. Has anyone had balljoint problems yet, or experienced this???

 

May be a caliper is got something getting it stuck or something, Id disasemble the brakes, clean them out, and see if it comes back after you put it all back together.

 

Thanks for the idea. I haven't dissasembled everything yet, but I've checked the pads & they're wearing even(still have plenty left, too), so it doesn't look like they're hanging up or dragging. The sound has been happening for about 15kmi now, so I don't think it's anything stuck in the caliper, but the sound hasn't become any worse, either????

 

Does it sound like its comming from the wheels or Under the hood? Ff from the wheels, is it left, right or bolth?

Do you feel anything in the pedal? (Suden pulse, or something)

Does the car brake adversly when it Pop's? (Quick loss of brak power, or quick increase in brake power)

Does it hapen only when braking in a straight line and not while braking in a turn?

At what average speed does it occure

Jack the car up getting both the front wheels in the air, put her on stands, start her up, get the wheels spinning, and get a Bud to look real close to see where the sound is comming from. Id do it with the wheels on and off. If its still comming from the brake, I would first disasemble clean and reinstall if any peice is causing a adverse effect, you should be able to correct it like this, BUT if it still persist after that, Id grab a caliper from a Junk yard (Under 50$) and swap em.

 

The sound is definately lower, not up high like a bad strut-mount. It does happen from either/both wheels, but I don't feel anything in the pedal....just a dull *bump* under my heels. And there's no effect to the braking.

It only happens after I've been braking moderately hard & then start to let up on the pedal....sometimes as I'm initiating a turn, other times while I'm coming to a complete(straight)stop. I'd say it happens after slowing to around 5-10mph, but it will also happen if I'm rolling about that slow & stab the brakes then ease off.

Good idea - I haven't actually tried to duplicate the noise with the car running & in the air...though I have a feeling it won't do it.

Honestly, it sounds like something must be moving slightly from the torque of the brakes & then popping back when I partly release the brakes. So I kind of doubt it will happen w/o any friction between the tires/road, or without the front suspension being loaded....but it won't hurt to try it!

 

My front brakes used to go knock knock knock as I was slowing. It was a rough spot on the rotor. I replace the pads, didn't turn the rotors and the noise went away for good.

 

Rusty, did that noise of yours repeat as you were slowing?

Mine only makes the sound once each time I stop.

 

I had a similar problem to this before coming from the back passenger side wheel. It would start at about 20 mph and do it until I stopped, sounded like metal on metal like Pete said. But all it took to fix it was taking off the wheel and putting it back on.

 

UPDATE:

While I was changing oil/flushing coolant last night, I ran the car w/the front end in the air. I accellerated up to around 30mph & braked, there was no pop when I eased back off the brakes....though it was kind of hard to tell, since even very light pedal effort would cause the brakes to lock pretty quickly.

I did notice that the instant the brakes made contact w/the rotors there was a visible(though not strong)quick pull of the steering wheel to the right, but it straightened back out....just sort of *bumped* to the right, and then immediately back to center.

I double-checked, and the car doesn't pull when driving/braking, so I'm wondering if it was just something to do w/having the front wheels unloaded/different length 1/2-shafts/etc.

 

Pete,

I replaced the ball joints on my 99 ES 2 weeks ago, it's got 185,000 km/115,000 miles on it. I didn't have any sounds like yours, just a clunk-lunk-lunk on washboard type bumps. There was enough play in them to feel when prying on them with a large screwdriver. Not something you want to change unless you're really sure you need them. Available only at the dealer, you have to change the whole control arm, parts for both sides, taxes in (15%) was $565.xx (CDN) About 1.5 hours to change them in my garage, (no hoist, but I do have an impact wrench)

 

Thanks for that info!

I only have ~1/2 the miles as yours(60kmi), and I can't feel any play w/a pry-bar, so I doubt it's the ball joints.

I'm starting to think it may be the strut mounts. With the car in the air, & tugging on the springs I feel a *very* slight wiggle.

Oh, and I was stopped on a downhill slope the other day, waiting to turn right(so my car was stopped at an angle on the slope). As I was stopped waiting for traffic, I turned the wheel a bit, and heard the same pop from the left-front corner....even though I wasn't moving at all.

 

I had a similar problem with my Taurus and it ended up being a worn tie rod end on the right side. Replaced it and the sound went away. I'd check for play there and also in you half shafts.

And that pop you heard when stopped on the hill, do you have a CAI?

 

No CAI.

I pulled the wheels off this weekend & checked everything. The only slop I could find was some flex in the back mount for the front control arm...has anyone else noticed if this is normal? My tires had some cupping wear on the inner tread, and I don't have any extra negative camber, or toe.

I also noticed that while the car was on stands, I could grab the top of the spring & move it slightly - making a sound similar to what I've been hearing. So I pulled out the strut assembly & took everything apart, but I'm not sure if what I found was normal: On other cars I've worked on, there's an actually "bearing" on the upper strut mount to allow steering rotation, but on this car there's only a greased *plastic* seat between the upper spring perch and the bottom of the strut mount. That plastic piece fits tigtly onto the top of the spring perch, but is very loose in the bottom of the strut mount - and it looked like there was some worn plastic bits in the grease(could have just been dirt, but appeared more black like plastic).

So has anyone had their strut assembly appart recently & remember how it's supposed to be?

 

I haven't had the strut assembly apart but the cupping on the tires is usually due to a worn out shock (damper).

 

The stock struts still have pretty good low-shaft-speed damping, but the high-shaft-speed response is going out the window.... I'll be getting new ones soon, I just want to make sure there isn't another bigger problem.

It seemed kind of odd that the cupping was only happening on the inside of the tread, though, since the suspension is completely stock & I've had the car aligned.