Brake issues

Howdy, I have a 2000 Tacoma 3.4L and am having some serious issues with my brakes.
Brake pedal is very spongy and I have to press very hard to stop.
When brake pedal is pressed at a stop, I can hear a hissing noise.
My brake light is on, but parking brake is off and brake fluid levels are ok.
I am assuming my brake master cylinder is going out, but no visible fluid leaks.
Any way to test brake booster and should I replace while I am replacing MC?

 

you said hissing when you push the brake pedal...You check your brake booster?

 

Vacuum hose leaking or booster is bad if its hissing

 

How can I check my brake booster?
Replaced all vacuum hoses on the engine within the past year.

 

Picked up a replacement brake booster and master cylinder, will dive into this after the holidays.

 

A spongy brake pedal and a hard application pressure .

Are 2 different problems.

Do you mean a long pedal travel then it gets rock hard ?

 

No, brakes stay spongy, pedal never firms up when pumped.
There is a hissing sound when pedal is depressed and sometimes the pedal will push back up.

 

Hissing noise is indicative of a failing brake booster.

 

Then dont drive it until it's fixed. You are flirting with disaster

 

But a spongy pedal is not.

A failing booster should have a very hard pedal.

Sounds like the system won't build pressure. Brake light on makes me think rear drums/ cable maybe way out of adjustment. Done any work on brakes lately?

 

No brake work lately and the brake light has gone back off.
If the system won't build pressure, does this indicate a leak or, again, failing booster?

 

Brake warning light reacts to master fluid level or e brake switch. If fluid level is good and float is not stuck, ebrake switch is next check

Not building pressure is high odds of a bad master. They can have an internal failure that causes fluid to bypass with no external leak.

 

Leak, bad master cylinder, or poorly adjusted drums. If it's an external leak you'll be losing fluid over time.

Booster has nothing to do with building pressure, it just amplifies the effort you put in at the pedal. When a booster goes bad, the pedal gets harder.

 

No visible leaks at the brakes or master cylinder that I can see. Fluid level has been fine and the e brake and cable are working correctly.
I got a deal on a master cylinder that came with a brake booster, figured if I was replacing one might as well replace both.

 

Well, is the problem solved?

We love to hear results, not just the problems. Helps everyone learn.

 

Same here......my bet is both master and booster is bad....

they say.... a failing master can leak right into the booster....thereby destroying it...


You're suppose to replace brake fluid every 4 yrs or so......So I guess I'm among the 1% ers......

be careful of buying a used taco or camry.......bunch just drive em til they fall apart......
thinking the 'Toyota' name will cover their sins.....

 

Had some personal issues in my life that have delayed this project, and I have been borrowing my dad's truck in the mean time.
Anyway, just pulled the booster today and realized the replacement I got from a 2004 was larger and used a different bolt pattern.
Called a local dealership and they told me the price for a new one was $1000.
I laughed at the parts guy and hung up.
Now I'm back on the hunt for a replacement, otherwise I'll just have to pick up an aftermarket part.

 

Yeah a generic one is about $100 bill.......

I've seen reman oem ones around $400....napa use to have those....

A autozone one with life......think where about $180 last time...

I bought an open box autozone one for $75 on ebay....
apparently these fit a bunch of toyota platforms pre 2001.....


Duralast Remanufactured Brake Power Booster 53-2581 (autozone.com)

About $180 if you work the 20 off coupon....and next day delivery.........

 

Replaced the master cylinder, filled up with new. fluid, and bled all four wheels.
Brake power is still very weak.
When I pump the brake pedal a few times, never feels very firm.
Hissing sound from booster is gone since I replaced the master cylinder.

Any ideas on next steps?
Could replace the booster but they are quite expensive.

 

Following. I've had spongy, low response brake pedal for years. No hissing. It has been suggested to check the rear shoe adjustment even though the parking brake is supposed to adjust them, which I have yet to get around to.