94 Caprice-antilock brake issue

[Dave_M]

I have a 94 Caprice Classic (125,000 mi.) and the antilock brake light has been on for awhile. It still stops, so I wasn't too concerned, but last winter it was obvious that the anti-lock feature wasn't working. (I live in western NY)

I had to take it to my mechanic for somthing else and I asked him to check into that. He said that "there's probably a piece of dirt in the valve assembly for the antilock brakes" and it's not repairable. According to him it's about a $500 part and I'm not about to spend that kind of money on this car.

I have always changed my own brakes because it's an easy way to save $$. When I told him that I changed my own brakes by simply prying the caliber apart with a big screwdriver to get the old pads out (as taught by my father) he said that's probably how I damaged it.

2 questions:
First, does my mechanic's explanation make sense? (I had changed front brakes on that car several times previously with no issues)

Second, I seem to have read someplace that there's a wheel sensor associated with anti-lock brakes that can get boogered up by rust and that can cause this symptom. Any truth to this?

Thanks...any input will be appreciated.

[CD Smalley]

You're on the right track with the wheel sensor. You need to get the codes from the ABS unit first before you start throwing parts at the thing though. I can't help with that. But google can I am sure....

[Dave_M]

Thanks CD!
Do you happen to know what type ABS system the Caprice has? (4 channel, 3 channel or 1 channel)

I would suspect 4 channel, but just don't know.

[CD Smalley]

3 channel if you are referring to how many sensors it has.

There are one for each front wheel and one for the rears. The rears are run from the pinion gear.

[1986Z28]

yes it is 3 channel i think, for codes ask formulalt1, i think he can help