It's been awhile, but a couple times I had to floor the brakes and barely make it to a stop. Pretty scary. It wasnt loose, but i pressed the brake booster in as snug as it could get it anyway. It got me thinking about how he car runs in general. Once a brake booster starts going bad, will it get worse and cause engine vaccuum issues, low idle, weird stats etc or is the worst what I've experienced and that's pretty much it. It hasn't happened in over a year but now I'm driving it more I don't want any scary surprises.

thanks

 

A failing brake booster will lead to those other things you mentioned, meaning typical vacuum leak issues (idle & A/F impacts, etc.), and eventually you'll get a hard pedal from having no power assist at all.

Not sure what you mean about "pressing the brake booster in as snug as it could get"...are you referring to the check valve where the vacuum line connects to the booster? In any event, what you described above (pedal going to the floor and still barely stopping the vehicle) sounds more like a failing master cylinder.

 

Thanks. Correct, i pressed in the vaccuum line to the booster as snug as possible. You think I might have 2 separate issues here?

The pedal to the floor hasn't happened since I snugged up the vaccuum line. Could the booster have any effect on the master at all?

 

Just to clarify, are you saying that you ARE having issues that present like a vacuum leak? Such as A/F metering issues, idle weirdness, etc.? Or were you just asking if those would be symptoms?

Because my initial understanding of your post was that the only actual problem you had experienced was the pedal going to the floor but barely stopping the vehicle. If so, then I think you only have ONE problem and it's not the booster. If the booster was leaking or had failed, you would see anywhere from a slight to a total loss of power assist (in addition to those issues related to a vacuum leak). The brake pedal would get harder to push, in fact getting to the floor would take enormous effort compared to how it would normally feel.

There could be several issues causing a low pedal/poor stopping performance (ranging from a failing master to ballooning flex hoses to a gummed up proportioning valve to other possibilities), but I wouldn't suspect the booster unless you have a hard-to-push pedal and/or a vacuum leak condition which can't be traced to anything else.

I've never see a vacuum line on one of those check valves come loose by itself. It's a barbed end on the check valve so you really have to yank at it to come loose.

 

Yes. Id say it acts up the majority of the time. I'll throw a few cans of seafoam into the gast tank and it will act normal for a tank or two. Then go back to being weird.

 

Seafoam wouldn't help if there was a vacuum leak (at the booster or anywhere else).

If you think there *might* be a vacuum leak at the booster, while the car is idling you can take a vice grip and pinch off the vacuum hose going to the booster. That will immediately halt any vacuum leak (and, if the booster IS leaking, it will quickly lose power assist and the pedal will get hard pretty quick, even if you don't depress it several times).

 

The seafoam definitely helped but youre right, would have no effect on vaccuum loss. I was attacking the effects of the supposed bad brake booster which def helped. Looks like I'm barking up the wrong tree

 

Do you know if there is any truth to the AT252006ERL brake boost check valve being better than stock GM valve (for brake boosting with turbo setup)