Brakes hard to stop!
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Drifting
Joined: Nov 2000
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From: always working
Brakes hard to stop!
I just got done putting the engine back in my 05 c6, got everything finished up and about to take it for a test drive. the brakes barely hold the car at idle! it feels like i have no vacum assist, but there are no leaks? I bled and vacume bled the brakes, Abs, And master but Still no difference. there is no air inthe lines either. I checked for vacume leaks but couldnt find or hear any... anything i should look for?
Btw, the car is completely Stock
Btw, the car is completely Stock
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Tech Contributor
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From: Charlotte, NC (formerly Endicott, NY)
Even if the power assist was completely inoperative you should be able to apply enough brake pressure to stop the car from speed let alone if all you have is an idling engine putting pressure on the torque convertor.
Bill
Bill
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From: Jacksonville Florida BWO Dayton, Cincinnati, Bloomsbury NJ, Cincinnati
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True but you might need 2 feet on the brake pedal to do it and still get a longer stopping distance. The rock of a pedal says no vacuum boosting from the cylinder.
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Melting Slicks
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From: Brentwood World's first A6 in the 9's (including N/A, blower, turbo and nitrous cars) 9.950@139.267 CA
I just got done putting the engine back in my 05 c6, got everything finished up and about to take it for a test drive. the brakes barely hold the car at idle! it feels like i have no vacum assist, but there are no leaks? I bled and vacume bled the brakes, Abs, And master but Still no difference. there is no air inthe lines either. I checked for vacume leaks but couldnt find or hear any... anything i should look for?
Btw, the car is completely Stock
Btw, the car is completely Stock
Melting Slicks
Joined: Aug 2006
Posts: 2,167
Likes: 11
From: Powell TN
Cruise-In VIII Veteran
The check valve is in the 90° elbow that is plugged into the back of the vacuum booster.
Thread Starter
Drifting
Joined: Nov 2000
Posts: 1,396
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From: always working
Thread Starter
Drifting
Joined: Nov 2000
Posts: 1,396
Likes: 15
From: always working
Thread Starter
Drifting
Joined: Nov 2000
Posts: 1,396
Likes: 15
From: always working
The car slows down to a Stop with hard pressure on the pedal, but it doesnt really clamp down and hold the car...
Melting Slicks
Joined: Aug 2006
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The procedure cycles the system valves and purges the air from the secondary circuits normally closed off during normal base brake operation and bleeding. The automated bleed procedure is recommended when air ingestion is suspected in the secondary circuits.
it was just a suggestion to the OP for trouble shooting
Melting Slicks
Joined: Aug 2006
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From: Powell TN
Cruise-In VIII Veteran
Did you pull the hose itself off or did you pull the hose with elbow attached out of the booster? If you take the elbow out, you should be able to easily blow in the end that goes into the booster (like you are trying to blow air into the intake manifold). If you try to blow into it the other way (trying to blow air into the booster) you should not be able to.
Thread Starter
Drifting
Joined: Nov 2000
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From: always working
Did you pull the hose itself off or did you pull the hose with elbow attached out of the booster? If you take the elbow out, you should be able to easily blow in the end that goes into the booster (like you are trying to blow air into the intake manifold). If you try to blow into it the other way (trying to blow air into the booster) you should not be able to.
I pulled the entire hose/elbow out from the booster, it pulling all kinds of vacume there.
I hooked up my Snap on Scanner and it has no codes, ran all the self tests and everything checks out
Thread Starter
Drifting
Joined: Nov 2000
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From: always working
not necessarily.
The procedure cycles the system valves and purges the air from the secondary circuits normally closed off during normal base brake operation and bleeding. The automated bleed procedure is recommended when air ingestion is suspected in the secondary circuits.
it was just a suggestion to the OP for trouble shooting
The procedure cycles the system valves and purges the air from the secondary circuits normally closed off during normal base brake operation and bleeding. The automated bleed procedure is recommended when air ingestion is suspected in the secondary circuits.
it was just a suggestion to the OP for trouble shooting
Safety Car
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From: Los Alamitos California
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No. You need a Tech II to completely get the last bit of "old" fluid out of the ABS channels. Like timid38, I have bled my brakes when I replaced the stock brakes with Stoptechs and didn't need a Tech II. My brakes are very solid.
San
San
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From: Powell TN
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The EBCM/BPMV (Electronic Brake Control Module/Brake Pressure Modulator Valve) or more commonly called the ABS unit operates 3 systems on your car, ABS, traction control and active handling. If you change the ABS unit or deplete the brake system of all fluid, then you have to use a Tech II to cycle through each of these 3 systems to completely get all the air out. If you did not let enough fluid out to get air into the ABS unit, then you don't need a Tech II to bleed your brakes. I am going to say that this isn't your issue because the car checks each system on every startup and will throw a code of it detects air in the ABS unit. Here is what it looks like:
This is the EBCM or computer half of the ABS unit. There are 3 rows of 4 sensors and each of the 4 represents one brake line. Each of the 3 rows represents the ABS, traction control, and active handling. These two pieces that make up the ABS unit are ~$2000 from the dealer.
This is the BPMV.
The round unit on the back is the brake pressure modulator which allows the computer to apply the brakes to an individual wheel. Below that is the brake pressure sensor.
Sorry, I know this doesn't answer your question, but maybe it helps to understand what it isn't and save you an expensive trip to the dealer.
This is the EBCM or computer half of the ABS unit. There are 3 rows of 4 sensors and each of the 4 represents one brake line. Each of the 3 rows represents the ABS, traction control, and active handling. These two pieces that make up the ABS unit are ~$2000 from the dealer.
This is the BPMV.
The round unit on the back is the brake pressure modulator which allows the computer to apply the brakes to an individual wheel. Below that is the brake pressure sensor.
Sorry, I know this doesn't answer your question, but maybe it helps to understand what it isn't and save you an expensive trip to the dealer.