The long story, I have 1995 SSE 168K. Three days ago I was driving home, about two blocks away, and on some ice, the ABS kicked in coming to an intersection. I ended up sliding into the intersection, a near death experience. I was going maybe 5mph. The left front wheel locked up and stayed locked. I was able to slide it into the driveway. In -20 weather I have taken the front left tire off, and caliper and noticed that with a C clamp I couldn’t compress the caliper. I figured it was stuck caliper. Bought a new one, replaced it, drove down the road two blocks for a test, front left locked up again. Brought it home, assumed some water was in the proportioning valve and it was stuck. Bled the right, and left front brakes. They seemed to bleed normal. Drove for 10 or 15 miles without a problem. Today when I had the car in the local repair shop, for something else, I had them bleed the breaks all around just to make sure there was no water, bad fluid, or air in the system. Drove home fine, skidded on some ice one block from the house, the ABS kicked in and the left front tire locked up solid again.

Where do I go from here? Is this an ABS problem, a bad proportioning valve? With my second vehicle dysfunctional, this is my only ride and I need to get a handle on it. Any help or guidance is appreciated.

Seems like a valve in the ABS pump is not releasing. Too keep you moving, the best short term course would be to pull the fuse for your ABS until either we can figure it out, or you take it in and have the ABS diagnosed.

You will still have normal operation of your brake system without the ABS, just remember you have to drive defensively, and be prepared for an emergency stop without ABS. Also, your going to have an ABS light on your dash now.

Speaking of which, do you have an ABS light illuminated?

While it does sound like something in the ABS system. It could also be a bad hose. The rubber brake hoses that go from the hard line to the caliper are known to degrade over time and they can act like a one way valve as the rubber collapses in. The additional braking etc may be enough to get the rubber to act like this and then release slowly over time.

I have seen and had this issue. Replacing the rubber hoses and rebleeding the system may be the fix for you. The hoses are typically about $12 each.

I get no ABS light. For now, I know I can release the pressure on the left by bleeding the brakes on the front right. I am going to disconnect the ABS for a day or so and see if I can get it to manifest itself again.

Having spent the last couple of days in the cold I am not looking forward to replacing the rubber lines, but will if I have to.

I will keep posting on the thread until solved, more ideas and suggestions are also appreciated, thanks!!!

Collapsed brake hose. Been there. It was even the same wheel as yours, the left front.

92 SSE
247k miles

Quick way to diagnosis brake hose is to get affected side locked up with tire off the ground then break loose the connection at the caliper where the rubber hose hooks in and if the wheel free'* up when loosened then you have a bad hose if the wheel does not free up with hose loosened then you have a bad caliper.

3 hoses takes it. I guess I will get my creaky old bones out on the driveway tommorrow and stick a new hose in. Suposed to be 11 and snow, almost like summer with the global warming in full effect. I will report the results back when appropriate. Thanks all!

Update to the saga…..

Replaced the brake hose today, in a blizzard I might add. Bled the line well and often. Drove down the block and skidded on some ice to test. The abs kicked in and the tire was locked again. I am assuming now it is an abs or proportioning valve problem. I pulled the fuses on the abs. When I get some more time I will drive around to test, and report back.

Thanks for keeping us updated. Be careful out in that new snow. It'* the other idiots you have to watch for.

Did some driving on this today (With the ABS fuse pulled). Did several hard stops. Could not get the left front to lock up. So now I have lots of questions.

Is it safe to assume that the ABS PVM is at fault? For some reason I thought there was an additional proportioning valve, but I believe (correct me if I am wrong) that the PM and proportioning valve are the same unit. The caliper and hose have been replaced, can’t think of anything else that could cause locking just on one side.

Looking at prices it looks like a PVM is $500 to $1000 and is probably a beast to put in. I have a 1995 Buick Park Avenue sitting in the driveway for a couple years that is going to the yard. I bet the PVM is identical, would it be worth pulling that one? Or is it just a waste of time, and I may be back in the same spot in a week or two.

Personally I hate ABS, and could live without it forever, but the wife drives the car so eventually I will have to fix it.

Again, everybody, thanks!