Brake issue, need help!

Well problem partialli solved!!

Can really tell yall wich caliper it was but at $40 each I just desited to replace them both :)

I still have a slight pull to the left but nothing like before!
It was just dangerous but its ok now.


Thanks for all the help, coments and suggestions !!
 
Well like I sead before problem was never solved @ 100%.

So after putting new fron calipers and new brake lines on the front of the car it still pulls to the left. A local shop took a look at my suspension and bushings and they sead all was good.

After putting in the new lines I noticed that while I was beading the front brakes the passanger side seems to have more pressure then the driver side.
Why is that?

So they told me that it must be the ABS pump that its not sending the right pressure to the calipers.

What do yall guy think?
 
So they told me that it must be the ABS pump that its not sending the right pressure to the calipers.

What do yall guy think?

BS

The ABS is only actuated as needed and isn't any cause for improper braking. The ABS only controls solenoids to control panic braking. It doesn't 'send' pressure, it only interrupts pressure.

But there could be a problem with the proportioning valve which controls the REAR brakes.

More likely the cause of any left/right pressure differences is the master cylinder. The master cylinder has primary and secondary systems as noted below.

Brake System, Anti-Lock

WARNING:
BRAKE FLUID CONTAINS POLYGLYCOL ETHERS AND POLYGLYCOLS. AVOID CONTACT WITH EYES. WASH HANDS THOROUGHLY AFTER HANDLING. IF BRAKE FLUID CONTACTS EYES, FLUSH EYES WITH RUNNING WATER FOR 15 MINUTES. GET MEDICAL ATTENTION IF IRRITATION PERSISTS. IF TAKEN INTERNALLY, DRINK WATER AND INDUCE VOMITING. GET MEDICAL ATTENTION IMMEDIATELY.

The Mark VIII is equipped with 4-wheel anti-lock brake system (ABS) with traction control as standard equipment.

The anti-lock brake system:

~prevents wheel lock-up by automatically modulating brake pressure during an emergency stop by not locking the wheels.

~allows driver to maintain steering control and stop vehicle in shortest possible distance under most conditions.

The anti-lock brake system consists of the following components:

~power brake booster (2005) and brake master cylinder (2140) assembly

~anti-lock brake hydraulic control unit

~anti-lock brake module (2C219)

~front brake anti-lock sensor (2C204)/rear brake anti-lock sensor (2C190)

~anti-lock brake pedal sensor switch (2C309)

Anti-lock brake system (ABS) operates as follows:

~When the brakes are applied, fluid is forced from the brake master cylinder outlet ports to the brake pressure control valve block inlet ports. This pressure is transmitted through four normally open solenoid valves contained inside the brake pressure control valve block (2C266), then through the outlet ports of the brake pressure control valve block to each wheel.

~The primary (rear) circuit of the brake master cylinder feeds the right front and left rear brakes.

~The secondary (front) circuit of the brake master cylinder feeds the left front and right rear brakes.

~If the anti-lock brake module senses that a wheel is about to lock, based on brake anti-lock sensor data, it closes the normally open solenoid valve for that circuit. This prevents any more fluid from entering that circuit.

~The anti-lock brake module then looks at the brake anti-lock sensor signal from the affected wheels again.

~If that wheel is still decelerating, it opens the normally closed solenoid valve for that circuit. This dumps any pressure that is trapped between the normally open valve and the brake back to the hydraulic control unit reservoir (2C246).

~Once the affected wheel comes back up to speed, the anti-lock brake module returns the valves to their normal condition allowing fluid flow to the affected brake.

~The anti-lock brake module monitors the electromechanical components of the system.

~Malfunction of the anti-lock brake system will cause the anti-lock brake module to shut off or inhibit the system. However, normal power-assisted braking remains.

~Malfunctions are indicated by one of two warning indicators inside the vehicle.

~Loss of hydraulic fluid in the hydraulic control unit reservoir will disable the anti-lock system.

~The 4-wheel anti-lock brake system is self-monitoring. When the ignition switch is turned to the RUN position, the anti-lock brake module will perform a preliminary self-check on the anti-lock electrical system indicated by a three-to-four second illumination of the amber CHECK ANTI-LOCK BRAKE indicator in the instrument cluster (10849).

~During vehicle operation, including normal and anti-lock braking, the anti-lock brake module monitors all electrical anti-lock functions and some hydraulic operations.

~Each time the vehicle is driven, as soon as vehicle speed reaches approximately 30 km/h (19 mph), the anti-lock brake module turns on the pump motor (2C256) for approximately one-half second. At this time, a mechanical noise may be heard. This is a normal function of the self-check by the anti-lock brake module.

~In most malfunctions of the anti-lock brake/traction control system, the amber CHECK ANTI-LOCK BRAKE and/or red BRAKE indicator(s) will be illuminated.

~The sequence of illumination for these indicators combined with the actual symptoms can determine the appropriate diagnostic tests to perform. Most malfunctions are recorded as a diagnostic trouble code (DTC) in the anti-lock brake module and assist in pinpointing the component needing service.
 
BS

The ABS is only actuated as needed and isn't any cause for improper braking. The ABS only controls solenoids to control panic braking. It doesn't 'send' pressure, it only interrupts pressure.

But there could be a problem with the proportioning valve which controls the REAR brakes.

More likely the cause of any left/right pressure differences is the master cylinder. The master cylinder has primary and secondary systems as noted below.

OMG !!!

I'm sooo frustated!!
 
I had a problem like this many years ago on a 1977 Pontiac I had, I did the caliper replacement thing etc. Turns out it was a failed component in the rear suspension. It was a crack in one of the rear leaf spring of all things. I guess my point is it could possible be something in the rear suspension.
Here in NJ they have a machine for the state inspections that does a brake balance test which measures the force on each wheel. Something like that may be useful to tell if it is a break pressure issue but I am not sure what shops would have equipment like that.
 
That reminds me....

The day that I took it to get traded in for that BMW the car felt slogish and when I got to the dealer about 45min away the back driver side tire was smoking.
The caliper some how got and was stock the hole way there.
After that day it didn't do it again.
Could that caliper be what wrong with the car and making the car pull to the left?
 
I think that is the side that the e-brake is on too, can't say if that is your issue.
 
If you suspect any caliper to be bad, address it first. But was it the caliper sticking or the actuator cable? Do you routinely use the e-brake?

My diagnosis of the master cylinder was based solely on the comment of percieved lower brake line pressure on one side vs. the other when bleeding the brakes.

Regardless, don't sweat it. Systematically eliminate the possible causes starting at the wheels. If there truly is a pressure difference in applying the brakes, the master cylinder is not that tough to replace.
 
I thought that the e-brake was on both rear tires? :(

Me too. ???

Cable Actuated Rear Wheel Parking Brake

The parking brake system is cable-actuated and controlled by an independent foot-operated parking brake control (2780). To apply parking brake, press parking brake control downward.

The cable-actuated rear wheel parking brake operates in the following manner:

An independent foot-operated parking brake control actuates the rear disc brake caliper (2552).


Part number 2552 is the RH i.e. drivers side caliper
 
Well That's good to know. My truck (with drum brakes) uses both.
I guess as long as it holds it from moving one is fine.
 
Unless you inadvertently left the e-brake on then the cable likely stuck slightly not fully releasing the cable on that side.

Worth looking into. You'll likely need an assistant to work the e-brake while you look under the car at the rear and see if the cable is working properly. It's a lot easier if you have the rear wheels on ramps and the front wheels chocked. Have someone apply and release the e-brake while you lubricate the cables with WD-40 and see if the caliper pivots are applying and releasing smoothly.
 
The question was "does it actuate BOTH rear brake calipers" ?????

+1

In the picture, the cable from the foot brake is black (just below the sway bar), and you can see both cables (attached to brackets in the sub-frame) going to the rear calipers above the exhaust pipes.
 

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Well after further axamination of the problem and several of brake test I saw that after doing some braking at hight speeds i noticed that the stearing wheel would shake after high speed braking.
Also while doing all this testing I noticed that while the car is rolling a squeek came out of the front driver side wheel and whent away after aplaying the brake.
So I desided to Re do My front brakes AGAIN!!
New pads and rotors.

So after that I whent to test the car out and the pulling seems to be gone from 0-50mph and after that there is a slight pull still but not as bad.

I wont know if its fixed untill I drive it some more.

Could that had been the problem?
 
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