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Do I need to replace vacuum booster?

J

jammy

New member
Hi:

Re: 1999 Grand Prix 3.8L

Here's what's happening:

  • Brake pedal goes to the floor, no resistance at all
  • No leaks under car
  • Reservoir was empty; filled it, pumped pedal and level dropped, but still no visible leaks.


From what I have read, this is most likely an issue with the master cylinder seal, and fluid disappearing without leaks means that the fluid is leaking into the vacuum booster.

Question: Does this mean I will have to also replace the booster when I put in the new master cyl?

Thanks!
 


Brake line(s) leaking

Sorry, the master cyl and booster were not the problem.

I found a leak in the line(s) where they go through a bracket just below the ABS module. It's going to be a bear to replace the line(s). Here are some pics.

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Given that the car is 22 years old (but a goldie!), what is my best course of action? Should I splice new line where the corrosion has occurred, replace the entire section or replace all brake lines?
 
im willing to bet all the lines that run to the back of the car are about shot to hell. be best to buy a brake line kit and a fuel line kit and replace all the old lines.

once you start touching them that old and rusty anther leak will start due to playing with them all.
 
Replacing brake lines '99 Grand Prix

Scottydoggs said:
im willing to bet all the lines that run to the back of the car are about shot to hell. be best to buy a brake line kit and a fuel line kit and replace all the old lines.

once you start touching them that old and rusty anther leak will start due to playing with them all.
Click to expand...

Scotty: As usual, you're right. I've searched for brake line kits and they look more than worth the risk of a future problem. Given the age of my car, I was considering the steel ones rather than stainless. Do you agree, or should go big if I'm going through all the trouble?

Now the important question: Can do this job without a lift? I have a hydraulic jack and 2 sturdy jack stands. Will it be possible by jacking up the front end, doing the front wheels and connecting the front half of the rear lines and then moving to jacking up the rear end and completing the rear wheels. The car has ABS, so will I be able to disconnect the module and get a bit more flexibility to maneuver?

Thanks again.
 
I would use stainless over mild steel anytime. If you have 4 jack stands you could probably get the car up high enough to work on it all at once
 
im thinking this isnt a trailer queen. with what im reading in the amount of rust, id go with copper. its real easy to bend and flare. might cost a bit more but the job is quick.
i replaced fuel lines on an '08 cobalt last friday. fuel filter to firewall. it took longer to get the old lines out than to install new copper. not factory match bends but pretty dam close
 


tomsteve said:
im thinking this isnt a trailer queen. with what im reading in the amount of rust, id go with copper. its real easy to bend and flare. might cost a bit more but the job is quick.
i replaced fuel lines on an '08 cobalt last friday. fuel filter to firewall. it took longer to get the old lines out than to install new copper. not factory match bends but pretty dam close
Click to expand...

Thanks for the suggestion, tomsteve. Sounds like the pros of Cu-Ni are ease of bending and flaring, cons are easily kinked and over tightening fittings. Definitely something I'll consider. Going to take the old lines off first and see how hard that is and how involved the bends under the hood are going to be (my car has an ABS module.) Wasn't thinking of the fuel line but probably should do that too. Is the fuel line the same diameter?
 
jammy said:
Thanks for the suggestion, tomsteve. Sounds like the pros of Cu-Ni are ease of bending and flaring, cons are easily kinked and over tightening fittings. Definitely something I'll consider. Going to take the old lines off first and see how hard that is and how involved the bends under the hood are going to be (my car has an ABS module.) Wasn't thinking of the fuel line but probably should do that too. Is the fuel line the same diameter?
Click to expand...

they only kink by misuse. ive used copper right off of abs units no problem. its pretty simple to not over tighten. what the pros do is not torque the **** out of the fittings right off the get go. no need to go all he man on em. just tighten them. check for leaks and tighten a little more as required.

fuel line should be a larger diameter than brake lines.
 
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