Hello,
I am having issues with 02 Alero. It has a 2.2L eng. The brake pedal is extremely hard to apply. I have replaced the brake booster, master cylinder, abs module. All calipers have been checked and are moving freely. Pads and rotors have been replaced. All brake lines are new from front to back. This has not resolved the hard brake pedal issue.

Any suggestions on possible causes of the brake pedal and what I can do to fix.

Thank you for your time.

Sam

well, you have obviously opened the system......there is the possibility of air in the system......have you properly bled the system?

before starting the car, pump the the brakes and hold your foot on the brake pedal.....do you have a high hard pedal? Now start the car.....does the pedal drop?

You have a hard pedal, does the vehicle stop ok from a high speed?

Is the red brake light or ABS light on? Have you scanned it for codes?

What was the original symptom, before replacing all these parts?

Hello,

Thanks for your reply! yes the brake have been bled properly. The pedal stays hard after being pumped with the enigne off and then started.

The vehicle stops ok from high speed but you really need to push the pedal. No ABS lights are on and no codes have been stored.

Original symptom happened suddenly. While on highway, the car suddenly slowed down and after pushing on the brake a few times it was ok. It did this a few more times at which point the pedal became hard. Took it to mechanic and the front right caliper was not releasing properly and was extremely hot compared to other wheels - verified with temperature gun. Mechanic replaced Master Cylinder and replace front pads/rotors. Car ran fine expect with hard pedal. Returned to mechanic and ABS module was replaced. Same Hard brake symptom. Then Booster was replaced. Same symptom. Lines were replaced last year and never has an issue.

Thanks

Vacuum source to the booster ok?

what did they do to fix the caliper, the others checked? did they check the check or replace the sliders?

yes, the booster vacum is ok. This is stumping a lot of people...

There was nothing wrong with the calipers. All pins were checked and each caliper was sliding freely. After the Master Cylinder and ABS were replaced, the brakes have been fine except for the stiff pedal.

Yes, I performed this test a few minutes ago. While car is off, I pumped the pedal 4 times and on the 5th I held the pedal down. While the pedal was down, I started the car at which point the pedal went down all the way. After pumping the pedal a few more times with the car running, it became hard again like it was before the test.

Hope this helps...

Thanks,