I have a 1990 Cadillac Fleetwood Brougham 350, 5.7 ltr engine rwd. My brake light came on and i checked the front and back brakes. I replaced the brake shoes and a bad cylinder in the rear. I also replaced one of the front calipers that was sticking. My brake light is still on, but when i bleed the replaced front caliper, the light goes off but comes back on as soon as the brakes are pressed. Also I see bubbles in the rear chamber of the master cylinder when the brake pedal is pressed. Can somebody help me on what i need to do? My brakes are locking up when pressed hard and pedal is soft and going to the floor.

 

I am going to assume you have bled the system properly at all 4 corners. If not, thats the problem. You have air in the system. If you do not know how to do the job correctly have a pro do it. Your life and someone elses may depend on it.
However if you have bled the system and if you are sure all the brake cylinders and calipers are not leaking. And all the brake lines are dry. You have a bad Master Cylinder.

 

aside from what was said above, the fluid is probably the original, 20 yrs old vintage .. suggest that you do a complete flush of the brake system. gummy or sticking components can often be traced to dirty fluid or moisture in the system.


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