2000 4Runner Ltd V6 Brake Help Please

[testshoot]

For a period of time my braking has deteriorated requiring more and more pedal pressure. Much worse when cold and after starting out. At it's worse, it is like bad manual brakes. I don't think it is anything on the wheel end. My guess is something in the master brake cylinder boost category. I haven't worked on brakes since manual brakes in the 60s. I know some systems use vacuum assist. Don't know how this one works, I just know it isn't that great...to the point of being dangerous.

Help appreciated...Thanks!

 

[thegipper]

Sounds like the brake booster check valve. When mine was going bad it would make the brake pedal rock hard on cold mornings. After a few pumps of the brakes it would free up and be normal again.

If that is the problem, make sure you replace the rubber grommet also. Super easy to replace and the parts are cheap. It was an easy fix.

 

[19963.4lsr5]

Sounds like the brake booster check valve. When mine was going bad it would make the brake pedal rock hard on cold mornings. After a few pumps of the brakes it would free up and be normal again.

If that is the problem, make sure you replace the rubber grommet also. Super easy to replace and the parts are cheap. It was an easy fix.

This happened to me also. On cold mornings at first start up.


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[testshoot]

Thanks guys, sounds like an inexpensive first shot at a repair. I hope it isn't the booster...I have a list of problems I am wanting to take care of.

The blend door valve, or whatever it is, which also operates the heater water valve under the hood.

And a muffler...

and...