bad power booster

[g33kfu]

I have an 02 silverado that is having some brake issues. When turning slow (i.e. pulling into a parking spot) and hitting the brakes the pedal is hard as a rock and I can hear the abs kicking in. When this happens there is no braking power at all. This doesn't happen all the time but it seems to be happening more and more often. I have considered taking out the abs fuse to see if it's an abs issue but i haven't yet. typically a hard pedal would be the power booster right?

thanks for your input.

[danielsatur]

If there's an ABS light indication, you lost your ABS safety feature, your break pedal should feel the same.

It sounds like your power brakes is the problem.

If the brake booster is bad, doesn't it lose vacuum, and the pedal will drop?

Try pushing the break pedal down with the engine off.
If break booster is bad, air will leak, and the break pedal should drop.

Also see Simular threads, at the bottom of yours.

[g33kfu]

I'm not getting any indicator or warning lights.

[danielsatur]

The vacuum comming off the intake is used to help the power assist break.

What's in between the Brake booster and the master cylinder?

[777stickman]

I agree with your thought of removing the ABS fuse for trouble shooting purposes. However you will loose the ABS function and will most likely turn the ABS lite on and set some ABS codes. Lots of post on here with similar issues. Fix being a wheel sensor or two. It would seem to me that a bad brake booster would be that way consistently and not erratic.

Let us know.

[j cAT]

Originally Posted by g33kfu

I have an 02 silverado that is having some brake issues. When turning slow (i.e. pulling into a parking spot) and hitting the brakes the pedal is hard as a rock and I can hear the abs kicking in. When this happens there is no braking power at all. This doesn't happen all the time but it seems to be happening more and more often. I have considered taking out the abs fuse to see if it's an abs issue but i haven't yet. typically a hard pedal would be the power booster right?

thanks for your input.

hard pedal is the brake booster is leaking or a loss of vacuum to it..

PEDAL TO FLOOR IS MASTER OR LEAK IN THE BRAKE FLUID SYSTEM.

question is do you have the system that works off the power steering pump ???????. If so you loose steering and brake power ..


since turning the wheels causes the abs to act up I think the front sensor wires are worn into the brake rotors ..plastic clips can come loose wires then get damaged..

[g33kfu]

Well I think i got it fixed. I had a bad wheel bearing on one of the front tires. The issue hasn't come back yet so I believe the play in the bearing was enough to screw up the abs sensor.

[j cAT]

Originally Posted by g33kfu

Well I think i got it fixed. I had a bad wheel bearing on one of the front tires. The issue hasn't come back yet so I believe the play in the bearing was enough to screw up the abs sensor.

when the bearing goes metal and rust foul the speed sensor which is a magnet..don't take long before the sensor is blinded by the metal debris.

where did you get the front hub bearing ?

[g33kfu]

I bought the replacement unit at Advanced Auto Parts. It is close to my house and they have free tool rental (I needed the axle socket). I did call around the the price was about the same.

[j cAT]

Originally Posted by g33kfu

I bought the replacement unit at Advanced Auto Parts. It is close to my house and they have free tool rental (I needed the axle socket). I did call around the the price was about the same.

you also need to torque this nut to I believe 157ft lbs . make sure to use a torque wrench . if not torqued correctly this may fail sooner ..

[doctorhrdware]

Originally Posted by j cAT

when the bearing goes metal and rust foul the speed sensor which is a magnet..don't take long before the sensor is blinded by the metal debris.

where did you get the front hub bearing ?

GM did a recall on the ABS system. The speed sensors were dirty and causing the ABS system to malfunction. This recall was like in 2002 or 2003. This type of speed sensor is replaceable, that is when I found out that the speed sensor can be replaced.

[g33kfu]

I actually did torque it down properly. Thanks for checking

[j cAT]

Originally Posted by doctorhrdware

GM did a recall on the ABS system. The speed sensors were dirty and causing the ABS system to malfunction. This recall was like in 2002 or 2003. This type of speed sensor is replaceable, that is when I found out that the speed sensor can be replaced.

the recall which did include my vehicle is about rust pushing the sensor out of position/out of the hole it sits in. It can do this because the sensor body is very soft plastic.

If you had this recall done , some reported it costing them 1700.oo...this is because they condemed the rotors/calipers/broke the sensor trying to remove it / and finally the hub ..

I did this TSB my self. 4years later the passengerside hub failed causing groaning noise which I was lucky to not have the ABS act up .

I got the hub for 70.oo it included the sensor/most do , as a matched unit. trying to replace the sensor only some have had to use shims because the sensor could/can hit the encoder wheel internal of the hub assembly.

when this is completed a sealant compound is applied over the sensor mounting area to prevent rust returning to cause all this from occuring again.

[doctorhrdware]

Originally Posted by j cAT

the recall which did include my vehicle is about rust pushing the sensor out of position/out of the hole it sits in. It can do this because the sensor body is very soft plastic.

If you had this recall done , some reported it costing them 1700.00...this is because they condemned the rotors/calipers/broke the sensor trying to remove it / and finally the hub ..

I did this TSB my self. 4years later the passenger side hub failed causing groaning noise which I was lucky to not have the ABS act up .

I got the hub for 70.00 it included the sensor/most do , as a matched unit. trying to replace the sensor only some have had to use shims because the sensor could/can hit the encoder wheel internal of the hub assembly.

when this is completed a sealant compound is applied over the sensor mounting area to prevent rust returning to cause all this from occurring again.

The dealership that we took the truck to came highly recommended from several friends. Did not have any trouble after the ABS repair was done.