95 Buick park ave?

Question

My brakes on the front passenger and rear driver work. I have good fluid pressure from master cyl on the rear line and non-existent on front line. I loosen lines comming off abs pump and fluid from rear 2 lines and none from front 2 lines.any help as im totally baffled.

Answer 1

A mechanic can power bleed them all four at once. It works.

Answer 2

You might need a new Metering valve(or combination vavle).Metering valves prevent the front brakes from applying braking untill the aproximantly 75-135 psi has built up in the system.The vavle is located in the line to the brake disc. Are you low on brake fluid?They have dual master cylinders where it runs on seperate circuits so if the rear brakes fail the front would still work.check to make sure you have fluid so you know its not leaking out .Other than that look into repairing the line, it may have been pinched closed somehow.If you take it to a shop and put it on a lift you will have a better visual of if its a pinched line.Good luck

Answer 3

If you can get your hands on the (TSB) Technical Service Bulletin # 535001A, it will explain what may be your problem with the ABS & ABS/TCS Pressure Modulator Valve Assembly.

Answer 4

THERE IS A SPECIAL BLEEDING PROCEDURE FOR YOUR VEHICLE,GO TO PARTS STORE AND GET THE PROCEDURE,IF YOU DO THE STEPS YOU CAN RUIN YOUR ABS UNIT BY NOT RUNNING IT PROPERLY.