Whistle while you work... your brake pedal? Brake pedal whistle. Video.

Video below.

'01 Tacoma 3.4L V6, 2WD. Non ABS, Auto Trans.

Whistling just started in the last 3 days. From what I've read here, this is pointing to vacuum leakage. I just wanted to confirm that this is related to possibly a seal/diaphragm and the brake booster.

Is the only fix here to replace the booster or a a seal/diaphragm at the break pedal at firewall connection to the rest of the brake system?

- Sound Up ^ ^ ^ -
With engine on:


With engine off:


Within 30 seconds of shutting off the engine, the whistling dissipates until it totally disappears which I assume is the pressured air running out.

PS - Pay no attention to the hair stuck everywhere. My dog leaves about a pound of hair in the truck every time he's in there!!

Thanks.

 

Certainly sounds like a leaking brake booster, the only fix is to replace it.

Make sure the master cylinder isn't leaking fluid into the booster, if it is you will need to replace it as well.

 

Thanks. How will I be able to tell if the MC is leaking into the booster? By taking the booster off and seeing if brake fluid is coming out?

 

Just unbolt the master cylinder, pull it back, and look for fluid down in the booster.

 

Got it.