Noise from left front wheel, and ABS light on

Subject: Noise from left front wheel, and ABS light on



Vehicles Involved: Ford Escape 2009, Mercury Mariner 2009



Condition: A clicking or rubbing noise from the left front wheel, and the ABS light may be on.



Repair: The ABS wheel speed sensor may be making contact with the reluctor wheel. This is caused by a defective knuckle, which miss-aligns the sensor and reluctor.



Remove the wheel and measure the air gap between the sensor and reluctor. If the air gap is less than .020 in. or inspection indicates the sensor has been making contact with the reluctor, the steering knuckle must be replaced. The installation of a new design knuckle from Ford should correct this problem.



TSB No. BPI 11-07

Grabby or touchy Brakes when applied and/or MIL light on.

Vehicles Involved: Cadillac, Escalade 2009; Chevrolet, Silverado, Tahoe 2009; GMC, Yukon, Sierra 2009



Condition: Vehicles equipped with two-mode Hybrid System may experience grabbing brakes or a touchy brake pedal when the brakes are applied. The ABS light may come on and a DTC C012E may be set in the EBCM.



Repair: The EBCM must be reprogrammed with the latest calibration available. Re-flashing the control module should correct the problem.



TSB No. BPI 11-06

94 jeep gc brakes

I have the vehicle listed above... I have completely replaced all parts in the braking system except the abs pump which still functions



Changed:

Power booster

Master cylinder

Proportoning valve

Rubber hoses

Calipers

Wheel cylinders

New rotors

Best non ceramic pads $ can buy on from and shoes on back



I can only get a semi hard brake pedal but I have pretty decent stopping(much better than before I changed the power booster)



Any thoughts on getting a more firm pedal??



Response:

On SOME Jeep Trucks on the rear axle where the brake lines connect is a "Limiter" that functions to allow more fluid to the rear brakes as more payload is gained. On others there is an electrical switch simular to a leveling device that controls the computer and ABS distribution. every wheel has a speed sensor that control each wheel by pressure and signal to the computer. If you have a Bendix System the Accumulator is part of the Pump Assy.

TSB 1987-2002 Dodge Dakota/ Durango Front caliper housing bolt

Condition: Caliper housing bolt damaged when servicing front brakes



Repair: When servicing the brakes and replacing the front brake pads some techs have complained that the hex head of the housing bolt because of its size M9-1.25 is easily stripped or damaged when they re-install the caliper.



The fix is to install an alternative housing bolt with a M10-1.25 hex head.



The bigger hex will be stronger and will facilitate installation without any issues.



The Raybestos part number for the M10-1.25 housing bolt is H5015W.

Brake problem with 1992 Chevy Lumina Car

the rear brakes on our lumina are shot we just bought the car and discovered the pads are missing and the rotors are severely rusted and pitted i do not even know if the calipers work.can the rotors be turned or is it just as well to buy new.any advice would be helpful thanks.



Response:

1) The rotors can be turned if there is enough metal left on them to be safely used. There is a minimum thickness which varies depending on the manufacturer. If you bring it to a shop, most will replace the rotors, just for the extra bux.



2) I would compare the price to buying them new. The cost of new rotors vs turning them on our van was only a $5 difference so we bought new.



3) Remember that with ABS Brakes to block the line and crack the bleeder screws before you compress and that they turn while compressing. You can rent the tool from most auto parts stores inexpesively. Myself, I'd replace the calipers just because my son has a 93 Lumina and know that they freeze up due to mounting hardware issues. The Hardware kit is cheap and easy to install to ensure safety. We replaced the rotors for $30 each(Borg), calipers were $40 each(Wagner), pads were $25 for the Lifetime Pads(Wagner).



4) I wouldn't open the bleeder screws... I'd take the cap off the master cylinder and push the cylinders back with a clamp(front) or rears turn them back with a special tool its a cube with a bunch of different prong arrangements and you turn it with a 3/8 ratchet... About 11 at most parts stores.... That way when your done its not necessary to bleed the brakes



5) You GO RIGHT AHEAD. The 1st time you have to buy a NEW Accumulator you'll have learned 1 expensive lesson about ABS Systems. And THAT Folks is WHY We block the lines and bleed off thru the bleeder screw.

Vibration after Replacement of new rotors

I recently purchased 2 new rotors for my suzuki grand vitara and had my tech install the new rotors, when I drove off… I had a shake in the steering wheel when applying the brakes and it felt like the brakes was slipping when pressing on the brakes. I took off the wheel to check for oil or dirt on the rotors and didnt see any oil/dirt on the rotors. I then took it back the tech and he install the old rotors back and didnt have the problem anymore. My tech informed me that the rotors wasnt a good set and where not balance and I needed to take them back to the store and get a replacement. Was this information correct that I was told?



Response:

This is accurate information. The new rotors you had put on were no good right out of the box, it happens form time to time.



The store should Brake Article

the rear brakes on this stratus and the right rear caliper will not release

I replace the rear brakes on this stratus and the right rear caliper will not release. There seems to be nothing wrong with the caliper itself. The pressure does not back off when you take your foot off the brake. I think it has anti-lock braking system. Any Ideas.



Response:

Is it only one side that will not release? How do you know that. Did you try squeezing the caliper back away from the pads?

1) Sounds like the rubber part of the line has collapsed,that line has a inner line that gets weak and when you press on the brake pedal it lets the fluid flow out to the caliper but when you let off and the fluid tries to return back the line collapses keeping pressure on caliper not letting it release...

2)And to prove this, get a c-clamp and push the piston back into the caliper. Remove the clamp and the piston should stay in the caliper. Start the car, push on the brake petal, turn the car off, and check to see if the piston stays in the out position. If so, replace the rubber hose. You will need to bleed the air out of the lines when that is done. Get some penetrating oil. I like Kroil, others on this list like PB Blaster. Spray the bleeders until you can loosen them. You will also need a friend to help with the bleeding.



3)

Do you know the the stratus has screw in rear calipers and not push in calipers???

2009 Jeep Grand Cherokee Brake Noise

My brakes make a horrible a screeching noise with light pressure on the brake. They’ve been inspected several times and I ‘m told my brakes are fine. I’m told the thickness of the brake pads is fine. They’ve blown off “dust” which didn’t improve anything. I’m told they can cut the rotor but you can only get one cut from a rotor. I can have new brakes installed but if I’m told my brakes are fine…why would I have new ones put on? I’m at a loss on how to remedy this situation. This is a new vehicle. Brake noise started at 8,000 miles. It’s a 2009 JEEP Grand Cherokee.



Response:

from a safety and function stand point, there is no need to replace the brakes. The brakes will perform properly.



You can have the brakes cleaned multiple times but unless you have the pads and rotors replaced, the noise will return over time.



I would ...read the entire brake article

2001 Audi A4 trouble starting

I have an Audi A4 2001. sometimes when I start it, after moving it, just cant start even though the radio lights came on. But after say one hour, when I try to Start the engine, it comes on.What could be the problem? And the brakes are hard to press.



Response:

Thus could be caused by a bad starter assembly. Best way to test this is to check for voltage at the starter when it will not start…. if it is getting voltage and not turning over, you guess it = replace the starter.



Brake pedal feel is firm, but brakes lack sufficient stopping power or fade

1.Check the operation of the brake booster and brake booster check valve. Replace worn or failed parts.

2.Check brake linings and brake surface areas for glazing and replace worn or damaged parts.

3.Check for seized hydraulic parts and linkages, and clean or replace as needed.

http://www.freeautomechanic.com/brakes.html

brake lights come on and go off

I have a 2004 Malibu and the brake lights come on and go off while i'm driving Just wanted to know where the problem is.



Response:

That Dash Light "BRAKE" doesn't always indicate a problem. If your Parking Brake is loose this light may flash as you drive or even remain on. If this light ONLY comes on while Applying the Brakes THEN you have a problem of either adjustment/replacem ent or Air in the system. A GOOD Indicator is if you must "Pump Up" the Brakes. This Light is controlled by a Proportioning Valve and NOT Cheap and Rare to go Bad.

Anti-lock brake problem

Hopefully someone here can help me. I have a 2003 Chevy Astro Van and everytime I use my brakes my anti-lock brakes kick in with their grinding just as I am almost at a stop. It is really annoying. I had someone look at my brakes a few weeks ago. He told me there was nothing wrong that my brakes are all over 50% and that it's just the anti-locks working when it's slippery. Well, it happens ALL the time, even on dry blacktop. I hope this is nothing serious or expensive. Any help is greatly appreciated.





Thank you!



Response:

1) my 07 f550 does the same thing and ford dont know why but has been doing this for 170000 miles with no other problems



2) Number one cause of this issue is a failing Speed sensor. The speed sensors are located inside the front hub bearing assemblies. This means you have to replace the entire hub bearing......



Or, you can just remove the ABS fuse or Relay to deactivate the ABS system. The ABS will no longer work which means it will no longer give you a problem when it is dry out. Just won't work in the wet, icy roads either. Once you save up the money, you may want to have the ABS system fixed.

How do I remove the rear brake drums on a 1999 Dodge Ram Van 1500 ?

After removing the wheel and tire, remove the clip from one of the studs. Bang on the drum and try to pull it forward. If it won't move, remove the rubber plug from behind, and adjust your shoes inward, with a brake adj. tool, and then try pulling the drum off.



http://www.freeautomechanic.com/brake-drum-brakes.html

issue with the brakes. The pedal is soft and tends to go to the floor

I am in Australia and we have a 97 Chevy Silverado that has been converted to right hand drive. We have an issue with the brakes. The pedal is soft and tends to go to the floor. We have changed master cylinders, pads, discs etc. etc. and now have bypassed the ABS and find that they work much better, but still a soft pedal. Our mechanic is wondering if there is a specific way of bleeding the ABS as this is where there seems to be some air that cannot be gotten rid of. Normal procedures are not working (normal in Aus anyway...) It is not an uncommon problem I believe in converted vehicles, but aside from being unsafe, our truck is now unsaleable until the ABS is reconnected and the pedal is firmer. Any suggestions would be appreciated. Already Tried: Bleeding brakes new master cylinder new discs new pads bypassing ABS

Answer:

The ABS system on this vehicle has always been problematic. There are a couple of things that will help when you bleed this system.

This is a two person procedure and may require a pint or more of brake fluid per wheel.

The old fashioned manual method with modification is best here, starting at the right rear wheel use a clear tube on the bleeder in a small glass of brake fluid crack the bleeder, have the person in the cap depress the brake pedal halfway never more and hold, the other person closes the bleeder and you both wait 15 - 20 seconds then the pedal is raised, the bleeder is cracked and the pedal is pressed, bleeder closed, pedal held halfway down etc. until all air stops coming out of that corner. Continue around to all the wheels in the same manner.

Once you have run a gallon of fluid through use a Tech2 scanner or a scanner that allows you to operated the automated bleed procedure in the ABS computer.

After doing the automated bleed procedure once go back and re bleed the wheels manually.

There are accumulator pistons in the ABS hydraulic unit that may be leaking, pull the small rubber cap from the two at the bottom of the unit and slide a small screwdriver in the hole until it bottoms on the piston and have a helper step on the brake pedal if the screwdriver is pushed out the piston is moving and the hydraulic unit is junk and must be replaced.

These systems are soft low pedals when they are working properly and have been the bane of many a mechanic over the years I will be glad to see the last of them in the junkyard.

99 olds alero is shuttering when the brakes are applied

99 olds alero is shuttering when the brakes are applied. I have replaced rotors and pads and still shakes. It does have a broken wheel stud on one of the front wheels. Also has 147,000 miles. Would wheel hubs need replacing?

Answer:

There may be an issue with the hub bearings. There are two ways to check a hub bearing. One is to swerve a bit left than right while driving about 15-25 mph and listen for a whirring noise and the noise will change pitch as you swerve. For hub bearings that are in worse shape, Simply jack up the front end and grab hold of the tire and try to wiggle it top to bottom, any play or movement at all is from a failed hub bearing.

Another thing that can cause this is a bad spot on a tire. Rotating the front tires to the back and test driving it should let you know if this is the case.

One missing wheel stud will not cause an issue.

How to trouble shoot a 1982 Chev K20 power brake booster problem?

Brake pedal feel is firm, but brakes lack sufficient stopping power or fade
Check the operation of the brake booster and brake booster check valve. Replace worn or failed parts.
Check brake linings and brake surface areas for glazing and replace worn or damaged parts.
Check for seized hydraulic parts and linkages, and clean or replace as needed.
VACUUM BOOSTERS Most power brake systems use a vacuum booster to assist braking.
Vacuum is good for a lot of things, like sucking gas through a carburetor, opening and closing airflow doors in a vehicle's climate control system, and for providing extra muscle for braking. But to assist braking, it takes a lot of vacuum.
How can something take a lot of nothing? After all, vacuum is the absence of atmospheric pressure. The answer is the higher the vacuum, the greater the atmospheric push to fill the void. As some famous scientist once said, "Nature abhors a vacuum." What he meant was as soon as you create a hole in the air (vacuum), the surrounding air tries to rush right in to fill it back up. So the push that a vacuum brake booster gives to the master cylinder is actually atmospheric air pressure.
At sea level, air pressure is 14.7 lbs. per square inch, which equals about 30 inches of vacuum on a gauge. The average engine can't pull that much vacuum, so the most intake vacuum you're going to read is about 20 to 22 inches. Most engines pull a steady 16 to 20 inches of vacuum at idle. One exception is a diesel, which has no throttle to create a restriction and thus no intake vacuum. So diesels have to use an auxiliary vacuum pump if they have a vacuum brake booster.
How the brake booster uses vacuum to provide power assist is amazingly simple. The original "Master-Vac" power brake booster that became the predecessor to virtually all vacuum boosters today was patented back in the 1950s by Bendix. The booster housing is divided into two chambers by a flexible diaphragm. A vacuum hose from the intake manifold on the engine pulls air from both sides of the diaphragm when the engine is running. When the driver steps on the brake pedal, the input rod assembly in the booster moves forward. This blocks off the vacuum port to the backside of the diaphragm and opens an atmospheric port that allows air to enter the back chamber. Suddenly, the diaphragm has vacuum pulling against one side and air pressure pushing on the other. The result is a forward push that helps shove the push rod into the master cylinder for power assist.
The amount of power assist that's actually provided by the booster depends on two things: the size of the diaphragm and the amount of intake manifold vacuum produced by the engine. The larger the diaphragm, the greater the boost. An 8-inch booster with 20 inches of engine vacuum will provide about 240 lbs. of brake assist.
From this, it should be obvious that the vacuum booster needs two things to do its job: a good vacuum supply from the engine, and a good diaphragm. A vacuum supply hose that's loose, leaky, collapsed or restricted may not allow the booster to receive enough vacuum to provide the usual amount of power assist. Consequently, the driver will have to push on the brake pedal harder to get the same braking as before.
A restricted vacuum hose will cause boost to drop off when the brakes are applied in rapid succession. This happens because the blockage slows the return of vacuum in the booster.
To check engine vacuum, connect a vacuum gauge to the supply hose that runs from the intake manifold to the booster. A low reading (below 16 inches) may indicate a hose leak or obstruction, a blockage in the exhaust system (plugged catalytic converter, crushed pipe, bad muffler, etc.), or a problem in the engine itself (manifold vacuum leak, bad valve, head gasket, etc.).
The condition of the diaphragm inside the booster is also important. If cracked, ruptured or leaking, it won't hold vacuum and can't provide much power assist. Leaks in the master cylinder can allow brake fluid to be siphoned into the booster, accelerating the demise of the diaphragm. So if there's brake fluid inside the vacuum hose, it's a good indication the master cylinder is leaking and needs to be rebuilt or replaced. Wetness around the back of the master cylinder would be another clue to this kind of problem.
To check the vacuum booster, pump the brake pedal with the engine off until you've bled off all the vacuum from the unit. Then hold the pedal down and start the engine. You should feel the pedal depress slightly as engine vacuum enters the booster and pulls on the diaphragm. No change? Then check the vacuum hose connection and engine vacuum. If okay, the problem is in the booster and the booster needs to be replaced.
Vacuum boosters also have an external one-way check valve at the hose inlet that closes when the engine is either shut off or stalls. This traps vacuum inside the booster so it can still provide one or two power assisted stops until the engine is restarted. The valve also helps maintain vacuum when intake vacuum is low (when the engine is under load or is running at wide open throttle). You can check the valve by removing it and trying to blow through it from both sides. It should pass air from the rear but not from the front.
Replacing a vacuum booster is a fairly straight forward job. All you have to do is disconnect it from the brake pedal on the inside and unbolt the master cylinder. The push rod that runs from the booster into the back of the master cylinder must have the specified amount of play, so check your service manual for the particulars. Most require a small amount of play so the master cylinder will release fully preventing brake drag, but some late model GM and Bendix applications have zero play.

Source: aa1car.com

How to change rear brake pads on a 2001 Mazda Miata

Question:
How to change rear brake pads on a 2001 Mazda Miata. I can't get the caliper to fully retract so I can put on the new pads.

Answer:
Sometimes you need to remove the brake fluid reservoir cap. This will allow the fluid to move so the caliper piston can be compressed. This happens when fluid has been added at any point.

Brake Replacement Step by Step with Photos

I have a 89 ford escort that has been setting for 10 years.

Question:
I have a 89 ford escort that has been setting for 10 years. want to get it going again but am having brake problems. Replaced brake booster. both rear wheel cylinders and shoes, both front calipers, master cylinder and cleaned the lines and I still don't have good brakes. I have to stand hard on the brake pedal to stop but it will not stop as fast as it should. Could it be the brake pressure control valves locates on the bottom of the master cylinder or is it something else. It just doesn't stop like it should in case of need to.

Answer:
Below is are quick diagnostic steps for hard brake pedal. You have done most everything but we need to take it a step further. Either the new booster is bad(it happens) or you do not have sufficient vacuum at the booster most likely caused by an engine vacuum leak. Since the car has been setting for some time it is more than possible for there to be cracked hoses, etc that are creating a vacuum leak. A higher idle than normal is a classic description of a vacuum leak.

Brake pedal feel is firm, but brakes lack sufficient stopping power or fade
1) Check the operation of the brake booster and brake booster check valve. Replace worn or failed parts.
2) Check brake linings and brake surface areas for glazing and replace worn or damaged parts.
3) Check for seized hydraulic parts and linkages, and clean or replace as needed.