cm0nkey

This occurs in any stop from 20 MPH or more:

In the last 10 feet of the stop the brake pedal depresses an extra inch or two very quickly and I hear a 1 second "BUZZ" sounds, the car then comes to a stop.

Anyone have any ideas, its very strange.

I have checked:

1. Fluid - Level was ok, turned off car Pumped 50 Times - level was above MAX line.

2. ABS / VSC system - Recently rebuilt my ABS speed sensors, all lights are ok.

3. Recently had front brake pads installed from Goodyear and an alignment.

Thanks,

kit cat

iTrader: (6)

you need muffler bearings.



















jk, that's normal. i think it's the brake booster of some sort.

cm0nkey

Awesome, thats a mere $1,348.59 from Sewell !!

http://www.lexus-parts.com/parts_det...id=22983&all=Y

qgoat

I would get the code read. I would almost bet one of your rebuilt abs/speed sensors is bad. Also, when you unbolt the sensor, clean out the hole the senor goes in.

kit cat

iTrader: (6)

he said "all lights are ok"...so i would assume no CEL.

Solo_D33A

I have similar if not the exact same problem, when I stop, I have the same pressure on the brake, but the suddenly half of the pressure on the brake disappears and the car rolls forward til you brake further down. No codes thrown, everything works, and it's not all the time it does that and it's only when you brake and coming to a stop and it'll happen at about 5 mph or so.

In my case, it's the rear upper ball joint, it's worn and boot opened, in which when I brake and coming to a stop, it gave a very slight movement on the wheel, in turn letting the ABS thinking 1 wheel is going faster = slip, which the abs turn on a bit, stealing a bit of our brake pressure, letting the wheel come back on track, and there's our (my) problem.

Note: I've also recently rerun the wires for my ABS sensor, and found this problem after, the sensors gave a fine signal, speeds are all correct.

cm0nkey

- Thanks sounds like we have a very similar issue!!

I had to rebuild the sensors for my car, I did not add any "grease" or whatever it is that goes on the tips of the sensors when I re-installed.

Also I built them myself and did not "Reset" the ecu at all afterwards, perhaps I should unplug the batter for a bit and try again.


Will let you know what happens with mine, and as I said no lights, but maybe I should go see if its still throwing a code?

cm0nkey

Really have no idea at this point, I am going to leave the battery unplugged for a few hours to see if resetting the ECU will change anything.

Car is throwing no codes but still has the wierd issue when braking.

If that doesnt fix it I will take it to the dealer, anyone know what I should expect to pay for them to tell me whats wrong??

Thanks

DarrellGS4

I have the same issue too...would be nice to know why. It can be scary at times to have that loss of break preasure feel.

cm0nkey

Wanna split the Diag fee

Where do you take your car, I have yet to go to a lexus dealer for service.
I am in Plano.

Thx

qgoat

Yeah. My bad. I didnt have a cel at first when mine started acting the same way as described by the op. I took the sensor out to clean and got the cel after that. Funny thing is when i got the cel the symptoms went away. It just basically turned off the abs/vcs system but the brakes worked great. I replaced the sensor and all is well now.

cm0nkey

Hey Solo_D33A & DarrellGS4 I guess we missed this post completely when searching (same problem as us, and a possible fix)

https://www.clublexus.com/forums/sho...+sensor+toyota



Thanks qgoat,

It sounds like you also had and solved our issue (Solo_D33A, DarrellGS4
, and myself, any others?)


So qgoat - What led you to the sensor in the first place, mine was real simple - the Ball joint failure ripped the sensor wire up..

And to confirm I understand (Before paying $275 per sensor) you had same weird braking issue, determined it was the sensor, took the sensor out (CEL light was on) - but braking issue went away, then replaced the sensor now CEL is off and funny brake issue is gone... Right?


Thanks alot for your help, hope this will resolve the issue for qgoat, DarrellGS4, and I.



--- ABS / VSS sensors ----

I have read that you can use Toyota ABS sensors with slight modifications and are much cheaper. Anyone done this?

Thanks!!

cm0nkey

Did you guys notice any white grease on your sensors when you removed them? cant find anything about adding grease before install.


________________________________________________


Anyway I took some steps off the net on this, modified them for our cars:



Cleaning the ABS Sensors and Ring - GS400

For cleaning, once you've removed the sensor, you're already half of the way there. Simply wipe off the grime with a degreaser-spritzed shop towel. Do not, under any circumstances, attempt to blow the debris off with compressed air! Static voltage can be generated, and then conducted to the ABS computer, which can damage it. Of course, you could disconnect the sensor to prevent this from happening, but why complicate things?

To clean the reference ring, use a small non-metallic brush and a squirt of degreaser. Make sure to go all of the way around the ring, and be thorough about it. If the rotor has been removed from the vehicle, its okay to carefully blow-dry the ring with compressed air. The ring does not need to be hospital-clean, just free of major debris and metal media, especially in the "troughs."


________________________________________________

Sample ABS Sensor:


FYI, I found the cheapest ABS sensors on RockAuto.com ($71.79)

1998 LEXUS GS400 4.0L 3969cc V8 MFI (H) [1UZFE] : Brake/Wheel Hub : ABS Transmission Speed Sensor

AIRTEX Part # 5S4770

http://www.rockauto.com/catalog/cata...IRTEX%2B5S4770

________________________________________________


How it works:

DarrellGS4

Well thanks, I never did any searching to check it, Mine recently started happening after I had to replace my caliper after a young and unresponsible family member went for a joy ride in my car. I'll have to check the abs sensor out and add it to his bill.

qgoat

I had a local shop replace my right wheel hub and bearing. Imediately afterwards I started having the aforementioned symptoms so I took it upon myself to try to clean the sensor instead of just taking it back to the shop and holding them responsible. After my atemp at cleaning is when I got the cel. I guess I completely killed it. I probably should have cleaned the reluctor instead of the sensor. Anyway, I got the correct part number for the sensor from my local lexus shop and then ordered it from oxygen sensors.com for I think 60 or 70 bucks. fyi the sensor is called a speed sensor. Hope that helps resolve your issues. Good luck and keep us updated.