Hello,
I have trailblazer 2007 4.2L.
I recently did some work on the front end (right wheel. replacing ABS sensor and some other suspension parts).
Negative battery terminal was disconnected before I started.
I had to take the caliper off to do the work and disconnect the brake hose.
I had the brake hose lightly crimped to prevent the fluid coming out - but not crimped enough as much of the brake fluid eventually leaked out.
I put back the front wheel together along with the caliper, reinstalled the brake hose clamp to the caliper with the washer.
I forgot that much of the brake fluid leaked out before I had someone pump the brakes to bleed the air out of the system while I was working the bleeder valves at each wheel.
Realizing that air is probably in the system, I went through many many many rounds of more than 1.5 quarts of brake fluid while bleeding out air from all 4 wheels.
No signs of leaks anywhere, especially at the front right wheel caliper, brake hoses and brake line where I did the work. Also, at the master cylinder the fluid stays at the same level when the brake pedal is pumped.
(I'm familiar with bleeding the brakes process as I have done it many times successfully)
The brake pedal still sinks down to the ground with no eventually resistance built up.
The brake pedal feels spongy, and I can hear lots of air noise when it's pressed.
I thought it might be the Master cylinder (my suspicion is it failed when bleeding the brakes with little brake fluid), but I'm just not sure about that as the brakes were working perfectly fine before I did the work.
The car has the ABS, which I had disabled many months ago as my front right ABS sensor needed to be replaced, which I did during this job.
The brake pedal just continues to sink to the floor with virtually no resistance.
I attempted to drive the car to see if there is any braking at all. There is some braking force applied at the end but just barely enough to stop.
Would appreciate any help.
Thank you
I have trailblazer 2007 4.2L.
I recently did some work on the front end (right wheel. replacing ABS sensor and some other suspension parts).
Negative battery terminal was disconnected before I started.
I had to take the caliper off to do the work and disconnect the brake hose.
I had the brake hose lightly crimped to prevent the fluid coming out - but not crimped enough as much of the brake fluid eventually leaked out.
I put back the front wheel together along with the caliper, reinstalled the brake hose clamp to the caliper with the washer.
I forgot that much of the brake fluid leaked out before I had someone pump the brakes to bleed the air out of the system while I was working the bleeder valves at each wheel.
Realizing that air is probably in the system, I went through many many many rounds of more than 1.5 quarts of brake fluid while bleeding out air from all 4 wheels.
No signs of leaks anywhere, especially at the front right wheel caliper, brake hoses and brake line where I did the work. Also, at the master cylinder the fluid stays at the same level when the brake pedal is pumped.
(I'm familiar with bleeding the brakes process as I have done it many times successfully)
The brake pedal still sinks down to the ground with no eventually resistance built up.
The brake pedal feels spongy, and I can hear lots of air noise when it's pressed.
I thought it might be the Master cylinder (my suspicion is it failed when bleeding the brakes with little brake fluid), but I'm just not sure about that as the brakes were working perfectly fine before I did the work.
The car has the ABS, which I had disabled many months ago as my front right ABS sensor needed to be replaced, which I did during this job.
The brake pedal just continues to sink to the floor with virtually no resistance.
I attempted to drive the car to see if there is any braking at all. There is some braking force applied at the end but just barely enough to stop.
Would appreciate any help.
Thank you
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