jarm

Every time I come to a stop, my right front pops when I brake. Is this a brake problem or the old standard control bushings? Thanks

Jman

wayman28

Do you feel any vibration or pulsing from the brake pedal when you come to a stop? Not sure you would hear control arm popping when coming to a straight stop without turning action of some kind.

Wandl

I'm suspecting the control arm (mine pops ever so gently)....

Nospinzone

This was posted a few years ago by a member, but do a search for actuator and you should find several threads describing the problem.

The TSB on the Actuator issue states that it could be a clicking or popping noise when stopping OR a squawk/popping noise after stopping and then pressing down on the brake pedal. According to the diagnostic specialist at my dealer, it is important to perform a correct bleeding procedure, which is apparently a step by step time consuming process per Lexus requirements. Your issue may come from the fact that the brakes were not bled appropriately, especially if the sound wasn't there prior to the brake pads being replaced.

jarm

Thanks for the help. Has anyone heard of this step before? When I had my brake pads changed, the mechanic did not bleed the brakes at all. We just changed out the pads and rotors and we were thru.

JDog

Wandl

While I doubt dirty brake fluid is the cause of the pop, I'd like to assume it would have been best practice to flush out the system while changing the brakes. Changing pads without bleeding the brakes may cause air pockets to form in the brake line (which can be dangerous) but again, I *don't* think that this would be the sole cause of your popping noise...

I'd have it checked again by a shop...whereabouts in TX are you? Here in DFW there are a good number of independent shops that I think forum members would vouch for..

jarm

I am in North Houston. Maybe someone can refer me to a good shop. M Performance is close to me and they work on all the very expensive cars. Maybe give them a try. I get no vibration when stopping, only a pop, pop, until completely stopped.

Wandl

Reach out to CL user LEXTEK1 he opened up a shop in Houston and, as his user name suggests, knows a thing or two about Lexus vehicles!
https://www.clublexus.com/forums/mem...5-lextek1.html

R Z

I also get that pop pop pop when braking. Car stops smooth and no issues, so I just keep on driving!

roadfrog

There's no way that just changing the pads would casue any air to enter the system. Unless you're disconnecting a caliper from the brake line.

That said, A proper brake system flush (WHILE CONNECTED TO TECHSTREAM), should be done every two years. Brake fluid is hygroscopic and needs regular change out to prevent rust and corrosion in the system....not to mention the reduced stopping ability.

AznRacer

iTrader: (2)

I had this same problem last month. Took it to the dealership and they said the control arms were bad. I got those replaced under warranty and now the same noise is still there not as loud as before. So I'm taking it back Tuesday hopefully they can tell me what's the noise is. I do have aftermarket rotors and pads I'm afraid they going to blame it on that so I'm keeping my fingers cross

Devh

Actually it's possible in this scenario because what happens is the fluid is pushed back when you compress the piston to make room for the new pads and water in the fluid will tend to shift and separate from the brake fluid. When the brakes get heated up it will boil in to a gas and that is where air is created in the system.

roadfrog

Hmmmm. I dunno. I cannot find one reference online to requiring a brake bleed for a simple change of pads (Edmonds, etc). Using your argument though, it should suffice, that changing the fluid every two years as required would negate this POTENTIAL. Or better yet, timing the two year interval with a pad change. I've done my own brake work on every car I've owned for over 35 years and this is the first I've heard of this (but your never too old to learn!) I can tell you though, that if you take your car in for a brake pad job, you better tell them you want the brakes bled, or it's not likely to happen.

Doublebase

I've never seen or heard of this. Brake fluid is hygroscopic for a reason, it's supposed to evenly disperse water throughout the fluid to prevent this scenario. I can't picture the act of pushing a caliper piston back in it's bore a half of an inch causing the moisture to molecularly free itself from the fluid. I have heard of dirty brake fluid being pushed back into the hydraulic control unit, damaging the valves, but even then I must say I've never seen that either. And I know you are supposed to crack the bleeder screw to prevent the fluid from doing just that, but then you run the risk of breaking the bleeder, or accidentally letting air in. I personally have never met a mechanic that cracks the bleeder screw open when pushing back a caliper piston - I know there must be guys out there that do it, and in brake classes it's mentioned - but I know of no one that does it.

I teach ASE preparation brake classes and I do tell them to do it, but I only mention it because that type of question may be on the exam.

I'm due for a brake change on my LS and at the same time I'd like to change the brake fluid, I'm hoping our Snap On scan tool can handle the job.

Devh

I think I should have explained it a little better. If you have good fluid in the system then you don't need to bleed the brakes when you change the pads. However if the brake fluid has taken in water as it will do over time, it has now reduced its wet boiling point. Overtime the water will boil and form a gas which will lead to a soft pedal. If the person who has bad brake fluid has not experienced a problem and they go to change pads then the fluid will shift and reduce the boiling point further and unmask the condition. I imagine it's probably from moisture and dirt in the system.
I have experienced this twice on friends cars where the brake fluid was improperly maintained. Once the cars were flushed the pedal was hard again and not compressible. The fluid that initially came out was thin, black and foamy before it turned to what looked like normal brake fluid.