M/c's have been crappy since the day I started driving a 9. I have been through so many m/c's on the car it isn't funny. You might recall a few years back I mentioned that I was given the wrong m/c for my car. The problem is that everyone else, now including me, has the wrong m/c on their 9's. The crappy replacment m/c syndrome is the reason I know that my car use to have the correct cylinder. Simply I had put on a dozen or so cylinders on the car for 26 years, without part's ordering issues. Suddenly after a quarter century 'my car's configuration is incorrect,' and all those high-end part-man professionals of days gone by, all lucked out and gave me the wrong one every time.
But how would I know about about how my car was made?
Your correct John and have been fishing in a much richer pond. A bad booster will allow the pedal to go to the floor. The only requirement needed to see how this is possible is to have a basic understanding of how a booster works!
The catch is that a bad m/c will make the booster sound-off as you say.
I use a different process than most when I'm troubleshooting. I know it isn't half the fun and half as impressive, but I like to start with the basics and conduct a few go/no-go tests. The real killjoy is that these tests ususally don't cost any money.
First of all, test your booster because it's easy, it's free, and it offers you a good starting point.
Disconnect that vaccume line from the booster and pull a vaccume on the booster. How you pull the vaccume is up to you. (I guess a pansyass--you know someone with a shocked look on their face say "Do you know what MOFO stands for?"--might have a problem with the test tools, but I disconnect the hose from the intake, and suck on it. Block it with the toung, and see it holds vaccume.) It's dealer's choice how you pull and maintain vaccume. The thing is that you're pissing in the wind if you start throwing parts at the car without verifying the booster holds vaccume.
If it doesn't hold vaccume, you need to repalce it. If you need to replace, you do not need to remove the hood. All it takes is a Craftsman brand 9/16" combination wrench, the one in even the most green shade-tree mechanic's tool box.
Here's a huge problem, and it may be the root/cause of yours.
I don't know why, but almost every pedal pumper applies a thousand times more pressure on the pedal than it takes to lock up the brakes, causing catostrophic failure to boosters, m/c's, w/c's calipers and brake hoses.
