Squishy Brake Pedal
Melting Slicks
Joined: Mar 2008
Posts: 2,351
Likes: 222
From: Delta B.C. Canada
2023 C7 of the Year Finalist - Unmodified
2019 C4 of Year Finalist (appearance mods)
2015 C4 of Year Finalist
Since the booster is a PITA to change, you'd want to first ensure that it's not a vac hose that has broken, split or let go. Also, you can use a dental mirror to check the booster for obvious cracks.
Drifting
Joined: Nov 1999
Posts: 1,324
Likes: 18
From: St. Peters MO
Try flushing the brake fluid by bleeding at least 1 quart of new fluid thru. Best method is a person inside pressing the pedal while someone else cracks open the bleeder at the wheel (RR,LR,RF,LF) don't let the master cylinder run out of fluid. Get clean fluid out of the first corner before proceeding to the next.
If booster was cracked, you would have to stand on the brake pedal to get the car to stop. But, as noted earlier, you can inspect it for cracks. They are plastic, and crack near the exhaust manifold side.
If brake pedal goes all the way to the floor, it may be the master cylinder is leaking internally. Or, massive amounts of air in brake lines.
If booster was cracked, you would have to stand on the brake pedal to get the car to stop. But, as noted earlier, you can inspect it for cracks. They are plastic, and crack near the exhaust manifold side.
If brake pedal goes all the way to the floor, it may be the master cylinder is leaking internally. Or, massive amounts of air in brake lines.
Thread Starter
Advanced
Joined: Oct 2008
Posts: 59
Likes: 0
From: banner elk NC
This couldn't be caused by a bad diaphragm inside the booster?
More information:
As far as i can tell the booster has no cracks, and no fluid leaks from the master or lines since, my master is topped off still.
Inside underneath the dash (where the brake pedal enters the firewall) is where i hear the most "hiss" and there is a rubber gaurd of sorts (not sure what it is) that covers the area. Im not sure if that gaurd has to be attached to something or not, but it is loose on my car.
The valve, where the vaccum takeoff connects from the engine, I can wiggle with my fingers (pretty sure if i tugged hard enough i could pop it out).
The level of "squishy" increases or decreases with the amount of time i drive the car or how cold it is outside. When it was snowing the other day i had to almost use both feet to get it to stop, and no i wasn't sliding.
This issue also happened overnight practically, if i remember right, i might have locked the brakes up or something.
More information:
As far as i can tell the booster has no cracks, and no fluid leaks from the master or lines since, my master is topped off still.
Inside underneath the dash (where the brake pedal enters the firewall) is where i hear the most "hiss" and there is a rubber gaurd of sorts (not sure what it is) that covers the area. Im not sure if that gaurd has to be attached to something or not, but it is loose on my car.
The valve, where the vaccum takeoff connects from the engine, I can wiggle with my fingers (pretty sure if i tugged hard enough i could pop it out).
The level of "squishy" increases or decreases with the amount of time i drive the car or how cold it is outside. When it was snowing the other day i had to almost use both feet to get it to stop, and no i wasn't sliding.
This issue also happened overnight practically, if i remember right, i might have locked the brakes up or something.
Race Director
Joined: Sep 2003
Posts: 16,836
Likes: 337
From: Database Error Indiana
Maybe squishy is not the right term ????? If the pedal is hard, like you said you needed 2 feet to press it, you have a bad booster. Its not hard to replace. Do a search for the best way.
Le Mans Master
Joined: May 2006
Posts: 9,226
Likes: 9
From: Irvine Ca
The level of "squishy" increases or decreases with the amount of time i drive the car or how cold it is outside. When it was snowing the other day i had to almost use both feet to get it to stop, and no i wasn't sliding.
This issue also happened overnight practically, if i remember right, i might have locked the brakes up or something.
This issue also happened overnight practically, if i remember right, i might have locked the brakes up or something.
Many members, and I do not know how, have done something that resets the ABS module and years of chasing poor brake performance disappears with a "click"
Sorry for not having more info on the ABS reset procedure, but think of it this way, your ABS is fighting you as it thinks one or more wheels may be sliding...so it pushes back against your foot as it is designed to do.
Thread Starter
Advanced
Joined: Oct 2008
Posts: 59
Likes: 0
From: banner elk NC
the pedal isn't hard...
it is squishy, with very little resistance, for the top 1/3rd or so of the travel and the resistance increases and you have a "hiss" noise. As you increase your foot pressure on the pedal the pedal becomes harder and begins to feel like a normal brake pedal
it is squishy, with very little resistance, for the top 1/3rd or so of the travel and the resistance increases and you have a "hiss" noise. As you increase your foot pressure on the pedal the pedal becomes harder and begins to feel like a normal brake pedal
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski