Soft brakes/Squealing noise sometimes
 

Hello Friends, I need your help and advice. I have a 2010 Acura TSX with 75,000 mile and it is almost 9 years old car. Recently I have been observing mushy or soft brakes - where I had to hit the brake pedal hard - so I took my car to my mechanic. At the shop the brakes were working fine again and the mechanic could not find the problem - He mentioned the car had 90% front Brake pads and 30% rear brake pads. He was under the impression that it might be a stuck stone type of situation but its been around two weeks and now my wife also feels the mushy brakes. I did check the brake fluid - it looks clean and is full. From time to time I do hear a squealing noise while braking but not all the time. I did notice the noise sometimes when I release parking brake and am reversing on my drive way which is on a slope. I suspect it could be the master brake cylinder or not sure If this is the case of stuck/freezing Caliper and if so not sure if I need to replace the front or the back caliper in case of a mushy brake pad situation? I am also not sure if it could be a problem with a brake line which exhibit similarity to a frozen caliper?

I am not an expert in cars but am currently frustrated as why the mechanic was not able to find the problem with my mushy brakes. I do agree it was working fine during the test drive with him and then started acting up from time to time.

Thanks once again for your help and support in this regard..

change the brake fluid....brake fluid is hygroscopic, meaning it absorbs water from the atmosphere.
the owner's manual states that the OEM fluid should be replaced after year 3. then yearly after that.

you can also check the rubber brake line hoses. rubber degrades over time. when the lines are old, they will start to expand, providing a mushy feeling.

the mechanic just looked at the pads and rotors and called it good, he did not investigate further... if he looked at the rubber lines, i bet they are expanding under the right conditions....ie; when you press the brake pedal... as the braking system is hydraulic

the symptoms for a bad master cylinder is the brake pedal going straight to the floor. You're not having this symptom, so I doubt it's the MC.
Check brake lines, replace brake lines and while at that, fill with new brake fluid.

Your pad or caliper slides might be sticking also. They should slide freely. A mechanic can help with that, if you are not comfortable working on it.

Though, its fairly simple.

That's probably the leading cause of spongy brakes.