Brake pedal goes to the floor?

Tiny
LAKOTA
  • MEMBER
  • 2010 CHEVROLET S-10
Chevy S-10, 89, 100K, V6

Three months ago I replaced the calipers, rotors, pads, on the front brakes and the cylinders, drums, shoes on the rear brakes. I also replaced the master cylinder and the combo valve (4WAL). The truck sat idle until a week ago. During that time we had a month of rain. The truck sat out side on a dirt driveway.

Now the brake pedal only travels about 2" and feels hard. Good vacuum, booster working ok. I opened the bleeders in the front, good squirt, pedal goes to the floor. I opened the bleeders in the rear and pedal feels hard and fluid trickles out. I opened the "T" connector at the rear and pedal feels hard and fluid trickles out. Fluid continues to trickle out when brake pedal is released. In both rear tests pedal did not go to the floor. Master cylinder checks ok.
Do you
have the same problem?
Yes
No
Saturday, August 11th, 2007 AT 11:48 PM

32 Replies

Tiny
MERLIN2021
  • EXPERT
Does the truck have a height sensing valve in back? If not combination valve is not centered. If it does the system needs to be bled with an ABS scanner that can open the valves internally in the BAS head unit. This guide can help.

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

Please run down this guide and report back.
Was this
answer
helpful?
Yes
No
Sunday, August 12th, 2007 AT 10:12 AM
Tiny
LAKOTA
  • MEMBER
Nope, no height sensing valve. I replaced the combo valve and the brakes are back to normal.
I posted this question on a few auto forums and got answers from, "Replace the calipers" You hit the nail on the head. Thanks Merlin.
Was this
answer
helpful?
Yes
No
+1
Sunday, August 12th, 2007 AT 10:59 AM
Tiny
MERLIN2021
  • EXPERT
No problem Lakota.
Was this
answer
helpful?
Yes
No
+1
Sunday, August 12th, 2007 AT 4:26 PM
Tiny
DORIS JENNINGS
  • MEMBER
  • 2008 CHEVROLET S-10
  • 2.8L
  • 4 CYL
  • 2WD
  • MANUAL
  • 105,000 MILES
Replaced master cylinder twice and replaced brake lines two years ago. Brake light does not come on when brake pedal goes to floor. No leaks I am aware of. I adjusted rear brakes everything worked before the replacement. Now goes to floor, why? I bench bled master cylinder. Could this be ABS module?
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
CARADIODOC
  • EXPERT
If the truck has four-wheel-ABS, you likely need to use a scanner to command the ABS computer to open two valves to allow the air to be expelled from those chambers.

Is your ABS hydraulic controller bolted to the ports on the master cylinder, or is it down by the frame and connected with two steel lines? What symptom led up to the need to replace the master cylinder?
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
CARPETMAN1759
  • MEMBER
  • 2002 CHEVROLET S-10
  • 4.3L
  • V6
  • 4WD
  • AUTOMATIC
  • 117,000 MILES
No brakes! Rusted out brake line to rear brakes at frame near exhaust manifold. Replaced with 12 inch flared tubing which is working great with no leaks. Installed a new master cylinder and bled the brakes. Great brake peddle until you start the truck and the peddle goes to the floor. Brakes were working fine until the hole in the line happened. Rotors, pads and calibers are a month old. What am I missing?
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
CJ MEDEVAC
  • EXPERT
Maybe it's your bleeding technique?

Here is the way I was brought up!

See this link

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

The Medic
Was this
answer
helpful?
Yes
No
-2
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
CARPETMAN1759
  • MEMBER
Used three different ways to bleed them. The gravity, two man pump and release the screws and used a vacuum pump. Gone through each method three times with no change. There cannot be that much air in the ABS system can there?
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
RIVERMIKERAT
  • MEMBER
At times, yes. Especially if you are not closing the bleeder screws properly.
Was this
answer
helpful?
Yes
No
-1
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
CARPETMAN1759
  • MEMBER
Been shade tree mechanic for forty years. I think I should be able to close bleeders properly by now. What ever the problem is I know it has to be something stupid.
Was this
answer
helpful?
Yes
No
-2
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
MHPAUTOS
  • EXPERT
Here is the bleed sequence as per Mitchel 1let me know how you get on.
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
CARPETMAN1759
  • MEMBER
I have this same write-up in one of my books. Have done this three times today and have great peddle after it is done, but when I start the engine the peddle just hits the floor when you push on the peddle. Thanks for your time!
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
SATURNTECH9
  • MEMBER
I went through this with a Suburban with ABS you can try and try to bleed the brakes did not happen. What you do is bleed the brakes like normal. Then you use the automated bleed procedure with a professional high end expensive scan tool. What they have you do is hold the the brake pedal while running the automated bleed procedure with the scan. Sometimes you have to do it more then once. It runs the ABS system to help purge the air out of it.
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
CARPETMAN1759
  • MEMBER
I was thinking my truck was to old to have that type of ABS. My truck is a 2002. The problem is I cannot drive it to the garage the way it is. I guess I could cut holes in the floor and use my shoes.
Was this
answer
helpful?
Yes
No
-1
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
SATURNTECH9
  • MEMBER
I have had pre-2000 vehicles requiring a scan tool to bleed the brakes. I wish there was a go around before I got my professional scan tool that did stuff like that. I had to turn away work because of it.
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
CARPETMAN1759
  • MEMBER
Thanks for the info! I guess I will find a way to get it to the shop.
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
JCSP86
  • MEMBER
  • 2002 CHEVROLET S-10
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 101,700 MILES
I changed my brake pads tonight and when I depressed the cylinder to allow the new pads to fit over the rotor I forced brake fluid from the reservoir. I have anti-lock brakes and think that when I forced that fluid out I messed the system up because now I can push the pedal to the floor every time I use the brakes. I have braking ability but it's not what I know it should be. Can you tell me how to reset the anti-lock brake system?
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
BLUELIGHTNIN6
  • EXPERT
You will need to bleed your brake while using a scan tool to open the ABS valves in the control unit. Here is a guide to help you when the scanner is connected.

https://www.2carpros.com/articles/how-to-bleed-or-flush-a-car-brake-system

Please run down this guide and report back.

Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
SATURNTECH9
  • MEMBER
You have tried your best to do it without it a scan tool. Unfortunately there are a lot of repair situations that require special tools. I wish it was not like that.
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)
Tiny
JCSP86
  • MEMBER
That did the trick thanks for the free advice I love this site.
Was this
answer
helpful?
Yes
No
Thursday, August 27th, 2020 AT 6:27 PM (Merged)

Please login or register to post a reply.

Sponsored links