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Brakes still soft after bleeding!

54K views 24 replies 21 participants last post by  jkeeney 
#1 ·
I installed new pads front and rear and follow the brake bleeding instruction from the M3 site. during the first bleed there were a lot of air bubbles and all the bubble are gone after the bleed. Pedal were firm, but as soon as I started the car the pedal went soft. I bleed the brakes again today, no air bubble. but still spongy. Any help or suggestion would be great. I used the pressure bleeder method.

tks
 
#3 ·
If you are pumping the brakes with the car off and you start the car it is always going to feel soft. When you start the car the booster kicks in making it feel soft.

I've had this happen to me before and it is very frustrating feeling.

Tim
 
#5 ·
the brake fluid reservior never went empty, I was using the Motive pressure bleeder. I tried bedding the pads already two 8 sessions of 60-10mph braking.

I bleed the brakes again yesterday with the the pressure bleeder first, the passenager rear had about 20 seconds flow of air bubbles, then it clear.

but the problem is with the driver rear, there were bubbles shootig out non stop for more then 20 mins, I had 2 liter of ATE blue racing in the pressure bleeder and it drained out almost all of it and I had to stop because the fluid were running low in the bleeder and my brother make sure the pressure is good throughout the whole bleeding process. I bleed out 1.5 liters of brake fluid and there were still a STRONG flow of air bubbles coming out from the driver rear. I then bleed the front two wheels, which no air bubble at all, then when I disconnected the pressure bleeder and did the step the brake and I release brake fluid there were no more bubble coming out of the driver rear or any wheel at all.

The brake is a bit firmer then before, but still spongy. I am thinking there might be a leak somewhere on my driver rear. Cause bleeding 20+ mins and there is still a strong flow of air bubbles that can't be right.

Any one have any ideas or what I could do to solve this problem?

I bleed the car twice already and follow the instruction from the M3 DIY site.
 
#6 ·
I have the same problem with my 02 330i. I bled the brakes three times using the standard two-man method. No air in the lines. Tried to bed the pads, and the pedal got a little harder, but it is still too soft for my comfort...and no where near the hardness before I changed the pads in all four corners.
 
#7 ·
I ended up bringing the car to dealer for bleeding. But to my surpise, after the dealer bleed the brakes, it feels the same way. Then I went to test my co worker's Z4 and found out that the factory felt the same way. So I did bleed the brakes correctly. lesson learn! ;( and $150 for the stealers!
 
#8 ·
I experienced something similar with my Saab 9-3. I replaced pads and rotors, without brake bleeding. When I drove it the brakes felt weak and mushy. I couldn't figure out how I got air in the lines by changing pads, but bled them anyway. No change. I took it to my Saab mechanic, told him the tale, and he promptly replaced my new pads with Saab pads and all was well.
The aftermarket pads were too 'hard' and didn't slow the car normally. To me they felt mushy because I had to push harder and the pedal felt like it went nearly to the floor.
 
#9 ·
I had the same trouble (see my earlier post). I bled the brakes again with the two man method. No air. The pedal is hard with the engine off, gets softer when the engine starts. The car stops OK, but the pedal lacks the hard feedback I expect, and had before the brake job. Is there a way to raise the pedal so it is higher? I hate hitting the brake, only to feel the car come to a stop with a pedal that still feels a little mushy.
If I had known this brake job was going to come out like this, I wouldn't have done the job.
P.S. I used Pagid brakes from Bavarian Auto. I did not run the MC dry. I used DOT 4 brake fluid. During my 65 years on this planet, I did about 2 dozen brake jobs, and never had this type of experience.
Has anyone told the Germans it's easier to put the tire on the wheel if you can sit the tire on a stud, rather than trying to get the rim hole in line with a hole on the rotor. And they almost won the war...
 
#10 ·
I had this happen to my car too. Replaced the rotors with OEM and the pads with Axxis Ultimate. Afterwards the brakes felt very soft, even though I didn't change the fluid. I bled the brakes and still no improvement.

Well about 4 months later I had to get the brake fluid changed for an unrelated problem. STILL no change. Now its 2 years later and I have just gotten used to having soft brakes on my car. I know that high performance pads don't have the initial bite of OEM, but this is far beyond what I expect and I don't blame the Axxis pads for the problem.

I haven't come to any good solution for this problem, I just live with it.
 
#12 ·
Same thing happened to me but I didn't bleed brakes after brake job. I got ceramic pads and Zimmerman rotors.

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#13 ·
Your master cylinder could be on the way out. I experienced this in a ford turbo diesel truck. With the engine off, the brake pedal got hard and never lost pressure. As soon as the engine turned on and the brake booster started working, it created so much braking power that the master cylinder would push fluid out the rear seal. If was such a small leak that you could never see it without removing it. It would slow the truck down but I had to pump it sometimes. I replaced the mc and the problem went away. Just something to consider


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#14 ·
That sounds like a lot of air, especially if you never ran the reservoir dry. I'd check to make sure all the bleed nipples are tight and your calipers aren't leaking. Spongy or not you shouldn't have any air in the system if you didn't let it in.
 
#15 ·
I'll tag into this thread, because I'm having the same problem.

Brief history: I've had problems with brake fade at the track. So I switched up to Performance Friction pads that are rated for full-on track use, and now I can't get the system to bleed to where I feel comfortable with it. I'm running the Performance Friction pads on slotted UUC rotors (should be "compatible"?). I ended up replacing the master cylinder last weekend and putting another 4L of fluid through it, and it's still only mediocre-feeling. The rationale for replacing the MC was that, after significant bleeding effort, I was getting a pedal that was mushy for the first push, less mushy for the second, and kind of OK by the third push. So even for street driving, I felt like I needed to push on the pedal twice to get enough stopping power to be useful.

My bleeding process is to use the pressure bleeder and the ScanTool from AutoEnginuity. I kick off the "ABS Air Bleed" process on the scan tool, then open the bleed valve and dump fluid into a jug while the computer cycles the brake system. I was doing each corner twice before moving on to the next corner, going RR/LR/RF/LF as per tradition. Then I went around and did the computer-aided bleed on each corner, but before going to the next, I'd punch the brake pedal HARD about 8-10 times (or until my leg gets tired). Punch fast, release slow, then go check the pressure and fluid level in the pressure bleeder.

After putting 4 liters of fluid through the system, it's safe to drive, but I feel like the pedal is going too far down, and it's just ... it lacks that solid feel. If I'm going to come into Turn One at 120 and hold my brake point until the last second, I'd like to feel Really Good about my brakes. Having done a bunch of brakes on a bunch of cars, I'm really feeling crummy about the brakes on this one. I mean, it's a BMW, right? It should have awesome brakes, right?

It occurred to me today that I haven't bled the clutch yet -- is that the One Thing that I'm missing? Or is there some bleeding trick I'm not doing that's causing me problems? Any hints or ideas?

Thanks,
Dan
 
#16 ·
Hey guys whats up, I just did stop tech pads and rotors up front with SS lines and brass bushing upgrade. Did a full bleed with a power bleeder at all 4 corners traditional method furthest from master cyl first. All bubbles are gone, fluid is nice and clean. Im 3 liters in and still have a spongy brake. Almost to the point of not feeling safe. I did the power bleeder 3 times and once with some help behind the brake pedal. Even with my brother behind the brake pedal and ten firm presses holing in on the last press I still have the spongy feeling. And still no air. I dont know if this is a dump question but is it safe to try bleeding with the engine running and pressurized and having someone hold the pedal down after its running??? Any help is much appreciated. I REALLY REALLY DONT WANNA WASTE MONEY AT THE DEALERSHIP!!!


Thanks
Bryan
 
#18 ·
06 zhp. Did a rotors, pads and brake flush/bleed this past weekend. Used Zimmerman coated rotors along with textar pads. Bled system twice (to my surprise a lot more air came out the second time around) and brake pedal is super spongy. Haven't bedded yet. (Waiting for coat on rotors to wear off per Zeckhausen Racing instructions). Anybody figure this sh*t out yet?! Reviving an old thread.
 
#20 ·
Still Soft

I realize this thread hasn't been active since last year, but did anyone ever come up with a solution?, I just did a 4 wheel pad & rotor job on my wifes 2000 323i, and I'm having the same problem, that soft spongy feeling pedal, I never allowed any air to be introduced into the system, but tried bleeding anyway with no improvement, I did a second bleed and went for a test drive, and I'm sure there was a marked improvement, this morning my wife takes off for work and shows up back at home 10 minutes later afraid to drive her car because the pedal felt spongy, I took it for a spin and sure as hell that soft spongy pedal was back, how is this possible!?!?!, If anyone out there ever came up with the answer, I sure could use it.
Thanx,
virgil
 
#21 ·
Jumping in on the old thread too... same situation for me. I replaced the master cylinder and did the bleed procedure twice, still have an inconsistent pedal. One press it's soft, slight tap, second press it's firm as I expect.

I did the booster test scenarios, all passed. I've replaced the check valve too. I get a nice firm pedal when I pump it up with the engine off.

Next step is to do the ABS module bleed procedure.

I'm posting because most threads I've found on the Interwebz don't show a resolution. The God fix has not worked for me... i.e. it just fixes itself after a couple days.

Any resolutions?
 
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