Brake peddle and stopping issues

I am experiencing a failure of my braking system on my 2016 2 wheel drive limited 4runner. The brakes will engage to stop the vehicle but when I come to a complete stop, the peddle starts to loose pressure and ends up at the firewall with the car inching forward towards the car in front of me. Took the vehicle to the dealership and they said all 4runners do this, and lined up 3 for me to see the same occurrence. I cannot believe that Toyota designed a braking system that 1. peddle goes the firewall and 2. that will not stop the car while at a stop in drive from inching forward.
Please help me, because it is obvious the dealer cannot.

 

I have a 2016 4wd sr5 and it definitely does not do this. That is not normal brake behavior.

 

Try another dealership. Your warranty applies at any Toyota dealership, should you still have warranty available.

 

That definitely isn’t normal. Have you noticed any fluid under the vehicle? Check the inner side of all wheels for signs of fluid. put it in park and climb under while having someone pumping the brakes. See if you can see fluid coming out anywhere. Also, check the brake reservoir for fluid level.

 

2018 2wd here. That is not normal. Air bubbles in the brake line?

 

What is actually happening here? Are you unable to control the vehicle at a stop/at idle? As in you've got it stopped, then afterward, while applying full pressure to the brakes, it pulls forward like your kid at Target when you've got one hand on his arm and another on his little brother and you've told him you're not buying toys? That's dangerous and should never happen.

If this is happening, don't drive your car and get it replaced immediately.

Are you at a stop and then, when stopped and idling, you have to apply a little more pressure to keep the vehicle stopped, because the vehicle "lurched" forward a little? (And by lurched forward, this describes the feeling of lurching as much as actual movement, which may be minuscule or non existent).

If this is happening, that's normal and NBD, although it absolutely drives some people crazy and makes then want to buy oversized brakes/rotors (although these come pretty beefy stock) to deal with "brake creep."

 

So, when you come to a stop, do you release pressure on the pedal even a little, and then it goes to the floor? In past experience that tells me a bad master cylinder. Definitely needs to be replaced ... and soon.

 

I notice the same with my 18 4runner, this didn't happen on my 08 FJ with close to 200k miles.

 

I have a feeling the OP is way over exaggerating what is actually happening.

Our 4R’s use a an accumulator system that does feel and sound slightly different then most traditional brake setups.

 

Definitely not normal. That is an accident waiting to happen.

 

Wish the other forum wasn't so shit. There was a good discussion on this very issue that I cannot find... From what I recall, the general consensus was this.

In order from cheapest to most expensive
- warranty
- bleed brakes
- change pads (Akebono were universally recommended)
- fancy directional rotors
- steal braided brake lines

 

That sounds like a bad master cylinder. I'm sure there's other things that could be wrong, but that is exactly what my MR2 was doing before I replaced the master cylinder.

It's would seem very strange for a master cylinder to fail so quickly, unless some debris got into it.

It could also be a leak in the system. Have you checked the fluid level?

 

It's a pressure problem. Could be air bubbles in the lines, fluid leak, broken master cylinder, it pretty much amounts to the same thing. You need to get your brakes fixed.

 

Lol nope something is wrong with the brakes buddy. Get it fixed. Take it somewhere else

 

My '14 felt the same way when I purchased it to the point that it was scary and my wife wouldn't drive it. Went the replace pad and check rotors, bleed, replace fluid, then replace with better (different pads and rotors) route. Not until it was all replaced did we feel confident with them.

 

I think there is a definite problem with your brakes. But it's weird how your dealer can come up with 3 4Runners that has brake problems.

When I was shopping for a 4Runner, the first one I test drove had weird brakes that seem to be pulsating even on gentle stops and it wasn't very good at holding the vehicle still while stopped.

The actual one I bought has pretty good brakes. Feels strong and holds my vehicle completely still. Even when I'm stopped on a down hill with the A/C cycling which cause the engine idle speed to ramp up and down, it doesn't move at all. My only compliant about my brakes is they are overly sensitive. Sometimes when I brake a little too quickly, it thinks I'm making a panic stop so all hell breaks look and it slams to a stop.

 

From your original post:

“The brakes will engage to stop the vehicle but when I come to a complete stop, the peddle starts to loose pressure and ends up at the firewall with the car inching forward towards the car in front of me.”

“Comes to complete stop”. If this happens with consistently seemingly normal peddle response, then the basic system (pads, calipers, master cylinder, vacuum assist).

“peddle starts to loose pressure and ends up at the firewall”. Could be a leak in a line or brake cylinder or master cylinder, but if the peddle is going down as fast as you say it is, your brake fluid reservoir should be empty and there would be easily noticeable fluid dripping out of a caliper or brake line or the master cylinder (check the inside of the firewall where the brake peddle rod goes through).

An internal piston seal in the master cylinder may be allowing fluid to leak past it (peddle slowly sinks) but is getting pushed back up into the reservoir. No external leak will be seen and the reservoir won’t be emptying out. If this is the case, it should happen consistently no matter if the vehicle is moving or not. This will also happen if the engine is not running (the peddle will get very hard to press once the reserve vacuum is used up, but it will continue to sink although it might move slower since the vacuum assist is no longer helping).

Possibly might be a malfunction ABS system (sensors, computer, valves) that lets pressure out because it “thinks” the brakes are locking up.

Maybe a leak in the power brakes vacuum assist. At higher engine speeds during deceleration, there is higher vacuum being generated which may be enough to compensate for a leak. Once the stop is complete and the slower idling engine isn’t creating enough vacuum to compensate for the leak.

Get in a big empty parking lot and try some experiments where you’re not risking running into someone. The more info you can give to the brake guy, the better they’ll be able to reproduce it and diagnose what’s going on.

Experiments.

When you come to a stop, keep your foot on the brake and then set your parking brake to keep the vehicle from moving. See if the peddle goes down (there may be an initial drop just as the parking brake is applied, but, once the parking brake is set, the brake pedal shouldn’t move any more).

When you come to a stop and the peddle starts sinking, quickly release the peddle and reapply it and see what happens.

When you come to a stop and the peddle starts sinking, shift into neutral (no forward force and slightly higher RPM and vacuum) and see what the peddle does.

Good luck.

 

Definitely not right.

 

I do this a lot at stops to keep hot pads off the rotors and extend life of the whole assembly.

 

If they had 3 more vehicles with the same thing happening it is a bigger problem than they want to admit to, it is not normal.