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Discussion Starter #1
Ok, so the other day the brake peddle sank to the floor and the brake light came on, things were a little spongy, next day peddle was still going to the floor but the car was stopping and there was a hissing noise coming from down below, next day brake peddle is stiff as can be and standing on it does very little. Luckily that happened as I was coasting into my driveway.

So, power assist unit right? Easy to change right? Anyone feel like changing it for me since I am one of the lucky ones that just had back surgery last week and will never again be able to tie myself in a knot to work on my baby..... :(

Seriously though, that does sound like the power assist unit right? Are there any trouble shooting tips to check before switching it out. The master cylinder looks newer if that makes a difference. I have only had the best car ever made for a year and the history on the car is a little fuzzy at best.

Thanks in advance for any advise :)
 

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The issues you describe kind of link both the master and the booster.

Have you popped the top off the master to check your fluid level? The brake would only come on if you had a low fluid level.

The hissing is a vacuum system symptom, as well as the labored braking.

So first check the fluid level.

Then, with the engine off, and you pumping the brake pedal, does the pedal get stiff under your foot after a pump or so?

If yes, then that's a good sign.

Then start the car while pressing on the stiff pedal. When the engine is running does the pedal get soft under your foot no matter how many times you press it?

If so, that's a good sign.

If the pedal never gets hard with the engine off that's bad. If it stays hard when you start the engine, that's bad.

BTW...I will be in St. Louis the morning of the 3rd, seeing a Rams game. Maybe we can stop by for a quick visit and see what you have going on.
 

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Discussion Starter #3
Hey there! Thanks for the response, the fluid level is all good, stiff peddle with car off, peddle stays hard when motor is on I think. I am going to get to messing with it this morning and see what I can come up with. I'll let ya know the outcome...... Thanks again for the info and the offer of help.
 

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Ok, heres what I know.....

Brake ped is stiff all the time now. With car off ped is stiff, pumping it doesn't make it any stiffer, when car is turned on ped stays stiff. At first with car at idle when I pushed on the brake ped with the car in park the engine died.... I adjusted the idle, now when the brake is pushed the engine just drops a few RPM.

I drove it around the neighborhood and I can brake but there is NO power assist, at all. I can still hear the hissing noise when I press the peddle.

Basically I am going to assume that the power assist is shot. Im going to save up some money and just take it in to our local corvette shop (Just Corvettes in St. Louis area) and have them fix it all up. I hate to spend all that money, but I'm just not able to do all that work due to my back and the fact that I have NO idea of what I am doing when it comes to the brake system on that car.
 

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Ok, heres what I know.....

Brake ped is stiff all the time now. With car off ped is stiff, pumping it doesn't make it any stiffer, when car is turned on ped stays stiff. At first with car at idle when I pushed on the brake ped with the car in park the engine died.... I adjusted the idle, now when the brake is pushed the engine just drops a few RPM.

I drove it around the neighborhood and I can brake but there is NO power assist, at all. I can still hear the hissing noise when I press the peddle.

Basically I am going to assume that the power assist is shot. Im going to save up some money and just take it in to our local corvette shop (Just Corvettes in St. Louis area) and have them fix it all up. I hate to spend all that money, but I'm just not able to do all that work due to my back and the fact that I have NO idea of what I am doing when it comes to the brake system on that car.

Yep that sounds like a bad vacuum booster.

What are your days off during the week or weekend? I'll offer to do the labor for free here in Columbia if you buy parts and bring it in.

Send me a PM either way, I'd love to help you out.
 

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"there was a hissing noise coming from down below"

If you have cruise fitted,this sounds like you have a leak on the cruise control to brake peddle vacuum pipe.:thumbsup:
 
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