Brake pedal sinking to the ground

I’ve had this 2012 Tacoma for about 4 months and now I have a sinking brake pedal. FYI I bought it with the ABS and traction control light on. (Never had any problems) I was told that they installed everything they could and could not get the lights to go out. So now This morning I began to hear a loud hissing sound the more I kept pressing onto my brake pedal. I typically have a 20 min drive to work and during the whole drive the brakes worked as they should. As soon as I started pulling into a parking spot, I started to hear a hissing sound as I began braking and the pedal started sinking. I did a quick test and started pushing on the brake pedal with the vehicle off and the pedal was solid with a really low hissing if I pushed hard enough. Turned the engine on and my foot began to sink to the floor. I couldn’t tell if the hissing was from the inside or outside of the vehicle. I was running late so I did a quick inspection of the MC and brake booster and it seemed to be dry with the MC full with fluid.
Any help would be greatly appreciated! Now I have to make a decision whether to drive home at 15-20 mph with hazards or get it towed from work lol. Thanks in advance!

 

This sound typical of a failed / failing vacuum brake booster.

 

Those malfunction indicator lights are not a suggestion or a casual reminder to fix it some day. Did you ever pull the codes to see what is wrong?

 

I have and from what I remember it wasn’t reading any codes. The lights were just illuminating

 

Is there anyway you know of testing the brake booster before installing a new brake booster?

 

Get someone to press the brake and listen to it. Look for a vacuum line that’s come off… you could get lucky. Fingers crossed for you. Booster is a PITA to get out.

 

That was going to be the first thing I was going to try when I got home. Cause it definitely sounded like a vacuum leak so I’m recalling hoping it just a hose of some sort.

 

Diagnose it.
Do a pressure bleed if you need to.

sounds like you might have an issue related to vacuum and/or the booster.

I have no idea what you mean by all these words about “they” and if that indicates any type of quality.

if a good “they” was involved you would know what is going on.

half of “they” are incompetent and unwise to associate with.

vacuum leaks can be smoke tested, listened to, and sprayed with brakleen, or scanned. Depends on the vacuum leak. One related to engine running can brakleen spray. Otherwise not necessarily.

I have replaced brake boosters on “PITA” German cars for other reasons. It was not hard.

 

https://www.wikihow.com/Test-a-Brake-Booster

https://www.youtube.com/watch?v=993AAOzHspk

https://www.youtube.com/watch?v=QaUPC8TjzWA

When you say the lights were on for no reason odds are you were incorrect. Rarely does the OBD Illuminate a warning light for No Reason. To get the ABS Code you need a scanner that can read them specifically, many average scanner do not read these codes.

 

Sorry for not being specific. By “they” I meant the used dealership where I bought the vehicle from.

 

They just wanted to sell you a vehicle...

 

You are 100% right I was trying to be to remember if any codes were on there but I can’t recall any. When I get home I’ll check to see!

 

Yeah and I was dumb enough to fall for it. But you live and you learn and I was in need of a truck so I pulled the trigger without really looking DEEP into it.

 

Make sure your scanner can actually read ABS Codes.

 

I wasn't trying to make you feel dumb. WE ALL do things we shouldn't and hopefully we do learn from it. I've done too many dumb things to even count.

 

As soon as I stepped out to my truck I seen a wet spot on by driver side wheel. Keep in mind, there’s been clear skies for the past 2 weeks and no need for AC either lol. I might’ve found the culprit

 

Don’t these have some fancy ABS that can go bad as opposed to earlier simpler pre facelift

their job is to sell the vehicle. It’s a used car dealership.

 

Time to figure out if it’s the brake house or brake line smh

 

With all the rust you may have bigger problems than just the ABS and traction control light. I'd start by looking at the frame, inside near the cats. Follow the exhaust up to the cats and then look at the frame, if you have the V6 look at both sides. Even if just the 4 cyl., look at both sides.

 

OMG. My 2012 looks brand new in comparison.

I'm glad you located the problem / leak.