99 Accord...pulsating in pedal when braking
 

Before anyone answers, please read what has been done to try to remedy this problem.

Car is stock, first of all, with 99k on it. Driven by a female and driven very easily.

Rear drums are new.
Front brake pads are new.
Front rotors are new.
Wheel bearings are perfectly solid.
CV joints are fine.
No bent tie rods.
Balljoints are in perfect condition.
Brakes were bled in case air bubbles were present. They were not.

Tires are wearing extremely well and very even.

Some people may think it's a bent rim or unbalanced tire but I have moved the front tires to the back with no improvement.

The brakes were replaced in hopes that it would fix the problem but has not affected it one bit.

Some untested thoughts....brake master cylinder...that's all I got left.

Re: 99 Accord...pulsating in pedal when braking (Justin Klemgold)
 

I've seen new rotors warped plenty of times; right out of the box!

Have the rotors resurfaced with an ON CAR BRAKE LATHE.

Re: 99 Accord...pulsating in pedal when braking (Justin Klemgold)
 

Pull the parking brake (lightly) when driving at the speed the brake pedal pulsates. Does it make the same pulsation? If it does, those new aftermarket drums are junk (no surprise there).

If it doesn't pulsate with the parking brake, your front rotors are probably warped (don't care if they're new or not), or you have excessive runout in the hub/rotor assembly. An on-the-car lathe will eliminate all runout in the assembly.

Forget about bent wheels, bad tires or master cylinders. Those items will not cause a pulsation. Now, an extremely loose tie rod and warped rotors will cause one helluva pulsation.

I should chronicle a few noteworthy events...

The car was pulsating and I was advised by my mechanic to change the rotors...the pads were fairly new.

So I put new rotors on. No change. So neither set of rotors are warped or are the problem.

Then since brake pads are cheap, I decided to replace them as well so I did that not an hour later. No change.

The steering wheel also slightly vibrates and "shimmies" when the brakes are pushed from a cruising speed.

Re: 99 Accord...pulsating in pedal when braking
 

Hell of a thread necro, but I have this same issue, did the op ever resolve this or anyone else have anything else I can try other than what's already listed?

Re: 99 Accord...pulsating in pedal when braking
 

I don't know if the inner tie-rod will cause pulsating but check the condition of the inner tie-rod.

Re: 99 Accord...pulsating in pedal when braking
 

Thanks, I checked that just now it feels perfect.

Re: 99 Accord...pulsating in pedal when braking
 

Pulsating breaks normally means the rotors are warped, which is caused by a distorted/bent hub which is caused by either over torquing lug nuts and/or hitting a curb or pot hole hard. You need to buy a dial indicator and watch some youtube vids on how to install it and use it to measure the lateral run out of the two front rotors. Either one or both will have .001 inches of lateral run out. Whichever have .001 inches of runout or more, replace the hub and the rotor and you'll be good to go.

Re: 99 Accord...pulsating in pedal when braking
 

From what I understand "warped rotor" is a bit of a misnomer, unless you are doing track days with your car the chances of that happening is remote, what does typically create brake judder is uneven pad compound being deposited on the rotor surface and the pads hitting these small speed bumps on the rotor surface which creates oscillation and judder at the brake pedal.

I have had the rotors skimmed, it didn't make a single jot of difference.
What I have noticed though is the one brake runs noticeably hotter than the other, I have stripped both callipers and the slides are smooth, the pistons are not seized.

Re: 99 Accord...pulsating in pedal when braking
 

You understand wrong then. Sounds like you've been reading that ridiculous stoptech article where they state rotors don't warp, then proceed to tell you why they do warp. No brake dust ever stays on brake rotors ever. Period. End of story. You've seen brake dust on the wheels, right ? That's an example of where brake dust can develop. Have you ever seen that on a brake rotor ? If you say, yes, then you're the only person in recorded history to have brake dust somehow develop on a brake rotor and not be scraped off on the next revolution when the pad again scraped the rotor when you press the brakes.

Re: 99 Accord...pulsating in pedal when braking
 

Wtf, what kind of idiot would conceivably think brake dust can cause shudder???
Where are you sucking this brake dust theory from?

Re: 99 Accord...pulsating in pedal when braking
 

From you.

Re: 99 Accord...pulsating in pedal when braking
 

Reread what I wrote, carefully.
Then seeing you don't understand what "pad compound being deposited on the rotor" implies maybe go read up about how disc brakes work and report back.

Also feel free to highlight where I mention brake dust :cray:

Re: 99 Accord...pulsating in pedal when braking
 

That's easy.

Re: 99 Accord...pulsating in pedal when braking
 

Yeah mate, thanks for pointing out I didn't mention brake dust anywhere??
I can see you are struggling but lets get through this together :popcorn:

Re: 99 Accord...pulsating in pedal when braking
 

Also don't forget my earlier advice, lets nip this in the bud : If you don't understand what "pad compound being deposited on the rotor" implies go read up about how disc brakes work.

Re: 99 Accord...pulsating in pedal when braking
 

When you quoted that stoptech article you didn't even realize what you were quoting ? lol

You're trying to school me on disk brakes when you're the one that came for help on how to stop brake pulsation ? lol

You don't even know what "pad compound" is. lol

Re: 99 Accord...pulsating in pedal when braking
 

Good day,

My auto gear shifter Knob had issues but I have changed the knob then came another issue, the shifter wont move into Park. What do I do?

Spyro76

Re: 99 Accord...pulsating in pedal when braking
 

Are the voices in your head telling you these things because I never quoted any article nor mentioned "brake dust" anywhere.
My aim was not to school anyone but then you pitched up and everything changed :wave:

Re: 99 Accord...pulsating in pedal when braking
 

Define "pad compound" as used by yourself here..

Re: 99 Accord...pulsating in pedal when braking
 

Guy comes in, ask about rotor warp, runout, brake pulsation, etc. Proceeds to tell one of the most experienced people on Honda-Tech how brakes work...After reading one of the most erroneous articles on brakes written by some haphazard Consulting Engineer how one of the most common issues just doesn't exist and it's all a big misconception.

If pad compound being deposited on the rotor was the actual issue, don't you think we'd be armed with brake cleaner out the ass in line shops and charge .5hrs per rotor for an "express cleaning service"? There is a reason on the car brake lathes and bench brake lathes exist.

Sit down and humble yourself before becoming an internet genius by reading a few articles in which you don't have the background knowledge to differentiate crap/misinformation from reality.

Re: 99 Accord...pulsating in pedal when braking
 

The braking compound on the brake pad
From the way you've been carrying on I can only assume you'll go to the auto store and ask the guy "I want brake pads with organic brake dust please?"
:cray:

Re: 99 Accord...pulsating in pedal when braking
 

Another genius mind reader fixated on some article that I never mentioned.
You are clueless if you think you could clean bedded brake pad compound off a rotor with brake cleaner.

Uneven pad compound deposits on the rotor is a widely acknowledged cause of issues that result in brake judder.

Re: 99 Accord...pulsating in pedal when braking
 

:thumbup:

reminds me of "you can lead a horse to water"

Re: 99 Accord...pulsating in pedal when braking
 

https://www.delphiautoparts.com/en/t....0Ou1PlaP.dpbs

Improper bedding-in:
Anytime you install new brake pads, it’s critical to bed or break them in by avoiding hard and excessive braking during the first 100 miles or so. This will help to transfer an even layer of friction material from the pad to the disc. Conversely not doing this can cause uneven pads deposits on the discs face, leading to uneven heat build-up. The high-spots can become very hot compared to the rest of the disc. If the temperature at these high spots exceeds 650°C, the cast iron changes structurally and transforms into a hard material called cementite, altering the discs make-up and causing the disc to wear unevenly.