Poor braking troubleshooting
Thread Starter
Instructor
Joined: Jul 2021
Posts: 238
Likes: 66
From: Frederick, MD
Poor braking troubleshooting
Hi all,
My ‘91’s braking is poor. I’ve been living with it for a while and it’s time to figure out why.
I have to hold the pedal down quite firmly at stops to keep from rolling forward (it’s an automatic, idle speed is probably a little bit too high also), and with all four wheels off the ground, pressing the pedal hard the rear wheels still want to turn a little bit when in Drive. It seems almost all braking force is going to the front because the car does stop ok, albeit not great.
I had replaced pads and rotors in the front, and pads in the rear, a few years back. They still look good.
I suppose I will start by bleeding the rear brakes. However I am also wondering if front/rear proportioning could be an issue. Is there a way to check?
Side note… while doing some testing today with all four wheels in the air, I noticed the rear wheels spin forward slightly even when in neutral. Is this normal??
My ‘91’s braking is poor. I’ve been living with it for a while and it’s time to figure out why.
I have to hold the pedal down quite firmly at stops to keep from rolling forward (it’s an automatic, idle speed is probably a little bit too high also), and with all four wheels off the ground, pressing the pedal hard the rear wheels still want to turn a little bit when in Drive. It seems almost all braking force is going to the front because the car does stop ok, albeit not great.
I had replaced pads and rotors in the front, and pads in the rear, a few years back. They still look good.
I suppose I will start by bleeding the rear brakes. However I am also wondering if front/rear proportioning could be an issue. Is there a way to check?
Side note… while doing some testing today with all four wheels in the air, I noticed the rear wheels spin forward slightly even when in neutral. Is this normal??
Le Mans Master
Joined: Dec 2005
Posts: 8,561
Likes: 945
From: Communist Colorado
You may need a new master cylinder. Is the pedal close to the floor when youre pressing it hard, or is it a hard, firm pedal? If its a real firm pedal, meaning no, or little power assist, then it could be brake booster related.
Thread Starter
Instructor
Joined: Jul 2021
Posts: 238
Likes: 66
From: Frederick, MD
The pedal feel seems normal. Power assist seems OK. Even if the booster was bad, the amount of effort required to keep the rear wheels from rolling is pretty extreme. I wish I could quantify these things, as "feel" is hard for anyone to trust me on. Front brakes grab much better than rear.
