Brake Booster

[TheBobmanNH]

So they say to test a brake booster, you should turn the vehicle off, and press the brake pedal a few times, and that it should feel consistent across all pushes of the brake.

My truck doesn't do this. First press is fine, second is harder, and third is rock hard.

But here's the thing. My daily driver (an '04 Subaru) behaves the exact same way. As does my girlfriend's car ('06 Civic). Granted they're all up over 150k miles, so I suppose they could ALL be shot, but.... seems suspect.

So,

1. Am I mistaken as to how to test this?
2. If this test fails, what exactly does it mean?

THanks all.

 

[Divh]

yes it will get harder with each pump of the pedal here is what i found with a quick web search if you like i can get back to you tomorrow with everything you need to do to test

Instructions
1
Turn the vehicle engine off and pump the brake pedal a few times to deplete any remaining vacuum in the power booster. Push and hold the brake pedal down with light but steady pressure. Start the engine. The brake pedal should drop slightly, indicating that the booster is working properly.

2
Allow the engine to run at idle for a minute or two. Turn the engine off and slowly pump the brake pedal five or six times. The brake pedal should stop at a higher position with each pump, indicating that the booster is not leaking and the check valve is working properly.

 

[TheBobmanNH]

Hmm. Thanks. I guess I just misunderstood the instructions I found after my own web search