so I have 95 4runner SR5 V6 3.0 that I have been the owner of since 2010. About a 2 years ago it started doing something interesting, the brake pedal goes about 1/2 of the way to the floor with minor braking, then it gets better after that, then when you hit the 5-10mph range the brake pedal kicks back causing it slow you considerably, then makes a clicking noise for about 2 seconds which can be felt in the pedal then the clicking stops and the pedal goes the rest of the way providing braking power.


Now the interesting part! It does the same thing in that speed range if you are decelerating but not using the brakes, I got up to about 20mph and popped it in neutral and let it slow down and it still does it regardless of whether or not the brake is pushed.
I've replaced the rotors and pads and a caliper on one side, which got rid of the terrible noise the brakes were making, but didn't do anything for the described problem.
About 7 months ago the brake booster went out which made the brakes insanely hard, it was all muscle stopping the car, so I replaced that, it made the problem go away for about a week then it crept back in. I've bled all of the lines till seeing clear fluid, there is no air in the lines, brake booster is relatively new, pads and rotors have less than 10k on them. I can not figured out what the issue is with the brakes...


I need your genius to help me diagnose the problem! Thanks in advance!

 

What is "the same thing"? Just the clicking noise? (If you're not using the brakes, I assume "the same thing" doesn't include any of the slowing or pedal action.)

I think you have more than one problem, so the first one I would look for is enough vacuum to the brake booster. Did you replace the rubber line? It could be leaking (which ought to affect idle) or blocked (which could reduce the available vacuum to the booster).

 

yes "the same thing" is the clicking noise that, when accompanied with breaking, kicks back through the pedal. so I just need start checking all my vacuum lines? and no I haven't replaced the lines as of yet, but will gladly go through the process if it fixes the brake issue. before I replaced the brake booster the idle was all wompy whenever I pushed on the brake pedal, but since I replaced it I haven't had a problem with idle.

 

Sounds more like ABS problems.

 

any way to test and see if its an ABS problem before I go and try to fix all the brake lines?

 

vacuum lines* not brake lines....

 

Make sure the rear brakes are ok and adjusted properly first. I've had ABS kick back the pedal like that on other cars & trucks. If the ABS light comes on check for codes.

 

New development, which may or may not be a contributing factor, which I'm hoping you guys might know something about. I removed the left rear tire the other day and took a look in the brake drum because that rim alone was black, and there is oil dripping in (not aggressively, at least it doesn't look like the pictures from ruptured axle seals I've seen) but oil none the less. So is there any way this oil being in one drum could be causing the problem? Messing with the ABS or something?

 

sounds like the rear speed sensor is not picking up a good signal, but it shouldn't be doing it when you are not using the brakes. does your cruise control work? i suspect there is a feed-back, probably a bad tail light ground or trailer wire converter. if the sensor or sensor wiring is bad, it should see the circuit problem and disable the abs, while illuminating the abs light on the gauge cluster. i would remove the sensor from the top of the diff and see if it's covered in metal. as for the oil in the left hub, it might be the brake wheel cylinder leaking you should be able to see if it is slinging out of the axle seal or if one of the wheel cylinder dust boots is full of fluid.

 

A '95 4Runner, if it has ABS, will be equipped with 4 wheel ABS. It will have tone rings and sensors on both axles, behind the wheel bearings.

Only the earlier two wheel ABS uses the single rear sensor on the 3rd member.

 

noted. do you happen to know what year they changed? i thought it was with the new body.

 

Can't say for sure. I have a wrecked '92 with the 2 wheel system.

It has the sensor on the punkin and uses power steering hydraulics for actuation.

My '95 has the all electric 4 wheel type.

 

This website: http://www.top4runners.com/index.html says that 4 wheel ABS
first became available on 4Runners in the 1994 models.

 

No the cruise control does not work, neither does the speedometer for that matter. I had assumed the issues weren't directly related so I didn't mention it.

 

check the fuses, then see if it works with the lights off. check the brake switch that it is working. it should be a mechanical (cable) guage, but if not, (if someone knows that the later gen2's have a digital spedo, please chime in) then there would be a speed sensor on the tranny that is not telling it how fast it's going. the thing is, no abs system with a problem and no traction control/stability control is ever going to energise if you are not pressing the brake (or it thinks you are) in the earlier gen2's all control modules get the signal via sensors, whereas the soedo is mechanical, so it can be inop (afik) and the computers still read the drivelilne speed and measure against the wheel speeds, etc. this includes the cruise control. so, if the system is otherwise good, but it is not working, it's likely seeing voltage present on the brake circuit, which could be a bad ground, or trailer wire converter. it's pointing more to this as a compound problem.

 

Did you properly adjust the brake booster push rod when you installed the new booster?