I have a new to me 2016 GS350 with 20K miles. The brake vacuum pump makes noise and my wife thinks the car sounds cheap, and she's right. I have never needed a vacuum pump to assist power brakes before, so why now? As long as you can get vacuum to the booster why the need for an extra pump? And if this is not a recall it must not be a safety issue according to the NHTSA, but sounds like it is not a pump fail just a poor design. Has anyone just bypassed it and run vacuum from intake to booster? My 1969 AMC AMX brakes work just fine with straight vacuum to the booster, why would this car have any substantial difference in engine vacuum to need the assistance of a vacuum pump?

 

We have variable length runners in our cars, right? This could be why, due to inconsistencies in the vacuum signal.

On that note, I believe I read once that the brakes have some computerized proportional valve that modulates the brake pressure to try and give a smooth braking "experience." If you're introducing pulses in the vacuum signal from a v6 vs a smoother vacuum, from what I'll assume is a vane-type pump, then you'll end up messing with the pre-programmed mapping of the brake modulation and it'll likely throw a code.

So, IMO you're screwed and will need to replace it.

What's the common point of failure on these things?

 

I do not see why runner length would change the vacuum of an engine. It will change where you make power in the RPM band but the vacuum would still be the vacuum based on an engines condition. Vacuum from an engine is enough to help a power brake booster, so why the extra pump? Usually you are on the brakes and at the same time you are off the throttle, under vacuum. Appears over engineered to me if it is just a feels better experience.

 

Ahh the noise only happens on cold starts. After warmed up, the sound will go away. I remember when I first bought my car it was pretty loud. When I switched to Penz Ultra Platinum it got a little quieter.

After the car is warmed up, it's just your standard 2GR direct injection ticking lol.