this just started recently. First i know that the ABS works well. Secondly, i know that there is a front left suspension piece that needs to be changed (i think tie rod).
So for some time i've been getting some break sqeaking in the front (when car is rolling) and goes away when brakes applied. Lately i've been getting a wierd symptom... i've noticed it occurs after i've turned left (but also on a straight-away), if i continue driving and SLOWLY apply the brakes i get this pedal-grinding feel, kinda like ABS for a second or so then it stops and the brakes begin to engage..very wierd and it happens on dry pavement....any ideas? thanks
fabs

 

Brake pulsation due to a warped rotor...or the pad worn out beyond the wear indicator...

I would first do visual inspection. Does ABS warning comes on when you turn the ignition switch to ON position?

There are other possibilities but with my beaten head this is all I can do for now[8D].

EDIT: My burned out brain rejuvenated itself for a split second.

Visually check for loose/broken/missing caliper slider bolts and caliper bracket bolts.

I may have another inspiration, depending on the neuron traffic conditions...


JPN

 

JPN...yes when i turn the car on, the abs/trac light are on and then they turn off....I will be bringing it in to get tthe brakes looked at. thanks
fabs

 

If your 850 is 93-95 model, you can retrieve trouble codes by yourself; no tool/instrument is required. If, however, it is 96 or 97 then you would have to visit a dealer. If it is engine code, you can visit local auto parts shop such as AutoZone and have them hook up their scanner onto your OBD-II port. Some of them may be able to access the ABS module for possible codes.

It seems that 93-95 models seem to develop problems in some of the switches, whereas 96-97 seem to develop cracks on the circuit board within the ABS module, close to the harness connection.

See if other experts could give you other alternatives.


JPN

 

I wonder if the ABS sensor is really dirty and when you apply the brakes the sensor thinks they are locked up and it activates the ABS.

Also are the front pads low?

 

Hey guys, i don't quite know what condition the front pads are in, to be honest, i've never done a brake job and i'm a little nervous...but if you have any steps i can easily do to find out, i'm more then willing to try...
When this braking problem occures i don't get any lights coming on the dash.....as mentioned when i start the car the TRACS and ABS are on and then go off... I'm thinking it may be pad/roter related like JPN mentioned
thanks
fabs

 

You do not have to be an expert to do a visual inspection; the most important thing to keep in mind is safety.

You can visually check the brakes by yourself but some tools are required.

- Keep the engine off & of course keep the shifter in P.
- Fully apply parking brake.
- Chock the rear wheels, if possible.
- With a breaker bar & a deep well socket (22mm?), loosen lug bolts x5, but keep them there.
- Jack up the front end with either the jack came with the car or a hydraulic floor jack is ideal (but do not go out to Sears or an auto parts shop to buy a cheapo). Should you decide to use the jack in the car, place something big under the car just in case. A truck tyre or something like that would be ideal. Lightly shake the car to make sure that it is secure.
- Remove the lug bolts x5 and remove the wheel(s).
- Visually inspect the thickness of the pads, cleanliness of the ABS pulser teeth (see attached), and try shaking the brake caliper for looseness.

http://volvospeed.com/850fbrake1.php

Wait till other guys chime in to get better perspectives.


JPN

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