Hey

I have a 93 850 GLT. It is the first car I have owned with ABS. Well we changed front and rear rotors and pads, since then the abs has been wierd....

I can hear the abs pump ticking from cold for a few minutes, this goes away but what scares me is that the pump makes a groan noise at low speeds. It can last from 1 to 10 seconds, but just groans, sometimes the pedal resists my foot. Then days can pass with no sounds at all.

Is something seriously wrong with the brakes?
No codes and the car slows down really well.

I really hope you can help
Mark

Hello all - I'd like to add on to On the ground's questions, because I believe I'm having the same isssue. I drive a 1998 S70 GLT w/ 99K.

I began having ABS issues about 3 months ago - I heard an intermittent grinding/groaning sound coming from the left front side of the car at low speeds (up to 35 MPH or so) under normal, dry driving conditions. Lasts anywhere from a second up to maybe 8 seconds. I also feel the grind/groan when it occurs while I'm braking. After a little while, the ABS & TRACS lights come on, and the sound stops coming. At first, the ABS & TRACS lights came on right away...after just a few blocks of driving. But every time I drive the car, it takes longer and longer for the ABS system to detect an error. Sometimes I'll drive it 10 miles and the lights won't ever come on.

Initially, I wasn't sure whether it was coming from the ABS pump (in the form of groaning) or the left front wheel (in the form of a grinding gear). So I took the car in to have them pull a code...they told me the computer was bad. Had Vic Rocha do his thing on the computer...he said the board was cracked, and he made the repair. The problem persists. And that's where I'm at now.

Another piece of possibly pertinent information: my left front CV boot is broken, and I have a click in that left front side, so I'm planning on making a repair to the CV Axle anyway. Could there be a correlation between that joint and the problem I'm experiencing?

Thanks to all in advance for your help. Abe

From my personal expierance I would look carefully at the abs pickup ring on both front axles. Remove the wheel and remove the ABS sensor from behind the rotor. If you can, place car in netural and rotate the axle around and look for a cracked Pulse ring or missing tooth. I spent hundreds trying to solve my problem, replacing calipers, Proportioning valves, ABS computer etc. before stumbling across the broken ring. Replaced both axle shafts with rebuilt units and problem was solved.

If that does not fix it you might want to look at replacing the splices for the abs that are located under the main fuse box in the cowl. I have not seen or heard of one in years but back in the day we did a boat load of them. The cure was to locate these two splices, cut them out, tin both wires and then solder them back together. Symptoms were low speed abs modulation, usually at 10 mph or less like when rolling through parking lots.

Mark