I think I have a problem with my ABS.

I would step on the brakes to stop (gradually) and the low traction light and abs inop would light up and my brakes would fail. I'll roll another foot and then stop. It feels like the abs is pulsing but only once.

I hope my explaination is clear.
So, anyone know what's wrong and how I can fix this?


Thanks

 

I have a black 1996 Z28 and I had the same problem a few years ago. The ABS wheel sensor is going out. I can't remeber which front wheel hub it is (L or R) but there is some type of ABS sensor that has gone bad. Mine was actually replaced under warranty so I can't give you any info on how much it can cost but I think that it is a pretty easy swap if you can get the part and do it yourself. Mine did the exact same thing as what you are saying, so I would say that it is the same problem.

 

If you need a part number, let me know, I think that I have kept all of my receipts, it may have the part number on it.

 

Thanks for the reply.
That's what I was afraid it was.
The problem is it doesnt happen all the time.
Any idea how I can test them to see which one or ones are bad?

 

I'm not sure. I am about positive that there is only one sensor, I just can't remember which side it was up front. I would say that it is the same problem because mine did not do it all of the time also. I'll look at my shop manual and see what I can find out for you.

 

The link below shows some good pictures of the hub itself. It is only held on by 4 bolts so if you can get the part yourself, it should be fairly simple.

http://shbox.com/1/front_hub.jpg

Here is your GM Part #7470587 Retail $136.28

 

There's one on each wheel actually.
I just spoke to my friend, he said I'll have to hook it up to one of those handheld diag thingies. Then drive it around to find out which one is bad since it doesnt happen all the time.

 

Ok, I did not realize that there were two, I quess it makes since now that there would be!

 

Could be as many as four.

I had a very similar problem with the sensor on the differential. It was in a Strange 12-bolt, and had to be adjusted for clearance to the reluctor gear. If it wasn't set just right, it would act exactly like that - car seemed to be stopping normally, the dash lights came on and the ABS kicked once, requiring just a few extra feet to stop the car. So... add the rear wheel sensor to the list. Possibly its coated with metal particals. If you have traction control, there's a sensor on each rear brake backing plate, none on the differential housing.

I would assume the EBCM control stores the trouble codes just like the PCM. You should be able to read the code, even it the light isn't on. Not sure though.