Dangerous ABS problem?

[guysk]

:-\ My girlfriend called last night and told me about a strange ABS malfunction. She tried to stop on a moderately snowy road (not ice) and her ABS kicked in - Only it didn't stop her! She heard the ABS whirring sound and felt the pulsating brakes but kept moving forward through an intersection. At first I thought that she was on ice and that was the normal functioning of the ABS. But after I asked her many more questions, I think that there really is a problem. The car is a '97 Legacy Outback that I bought for her a few months ago.

 

I have an 88 BMW that did something similar. When I was going slow and I stomped on the brakes, the ABS would kick in and barely stop the car. I pulled a couple relays under the hood to disable the ABS and never gave it a second thought. But I want her soob to have the ABS working.

 

Has anyone else experienced this and what could the problem be?

 

Also, she is four hours away needs to get home safely this weekend before I can look at it. Is there a fuse that she can pull to disable the ABS for the drive home?

 

Thanks,

 

'97 Legacy Outback 2.5L, 144K

[Glenner55]

I believe there was a recall on Legacy brakes from that year, may want to check with the dealers. If you haven't found these guys yet you may want to call Auto Creek in Vergennes. They are Subaru specialists, I've used them

in the past and they really know their stuff also have used parts available if needed.

 

Glenn

 

 

 

:-\ My girlfriend called last night and told me about a strange ABS malfunction. She tried to stop on a moderately snowy road (not ice) and her ABS kicked in - Only it didn't stop her! She heard the ABS whirring sound and felt the pulsating brakes but kept moving forward through an intersection. At first I thought that she was on ice and that was the normal functioning of the ABS. But after I asked her many more questions, I think that there really is a problem. The car is a '97 Legacy Outback that I bought for her a few months ago.

 

I have an 88 BMW that did something similar. When I was going slow and I stomped on the brakes, the ABS would kick in and barely stop the car. I pulled a couple relays under the hood to disable the ABS and never gave it a second thought. But I want her soob to have the ABS working.

 

Has anyone else experienced this and what could the problem be?

 

Also, she is four hours away needs to get home safely this weekend before I can look at it. Is there a fuse that she can pull to disable the ABS for the drive home?

 

Thanks,

 

'97 Legacy Outback 2.5L, 144K

[outback_97]

Guysk:

 

A couple of times I have had a similar experience in my car although not as severe, not sliding through intersection. Just yesterday, in fact, I was pulling into a parking spot that hadn't been plowed, hit a patch of ice, and the ABS seemed to "disconnect" my brakes for a second, as I kinda slid into the spot. Disconcerting! Once, a similar and almost very bad thing happened when pulling up to a stop sign, where they had worked on the road and there was a 2 or 3" drop like this -----_____----- in the road surface... when the front tires went over it while braking, ABS kicked in and reduced braking ability a lot. Almost hit the car in front of me, not cool.

 

I've tried playing around with it in controlled circumstances (empty roads and parking lots in snow / ice conditions) and in my experience you have two options: 1) Lift brake foot and reapply, like pumping old pre-ABS brakes just at the friction limit to avoid a skid. Or, 2) Push down the brake pedal even harder while the ABS is doing its thing, this will decrease stopping distance as the ABS seems to be too sensitive and will kick in even when there's not much pressure on the pedal.

 

There's been many threads on Nasioc (another Subie msg board) with people concerned about the ABS in WRX's primarily. The behavior of my 97 OB is similar to the problems that people describe with the WRX, IMO. This is my first ABS equipped car that I have owned so I don't have a lot of experience with how it compares to others. I sometimes consider pulling the fuse but haven't done that myself.

 

Steve

 

EDIT: Glenner posted while I composed my long-winded post. I'm not aware of any brake recall pertaining to my '97 Legacy OB, that would be the first I heard of it. Glenner, any more info on that?

[Ranger83]

How can you do this on a 97 OBW? Does the AWD system use the ABS sensors?

[Legacy777]

There is a fuse you can pull to disable the ABS system. It should be under the dash. If she has the owner's manual, have her look in the back portion where it lists all the fuses. There should be one listed for abs.

 

As for the behavior.....honestly....sounds normal. ABS in snow & ice isn't that effective. The suggestions given above on what you can do, press harder, or lift & reapply are good suggestions.

[Hondasucks]

The ABS is there to keep the brakes from locking up, and sending you out of control, it does not really increase stopping distance (Unless you are one of those people who mashes the pedal to the floor and holds on for dear life in a panic stop, instead of pumping the pedal like you are supposed to...), it is just there so you maintain control in low traction situations. Ice, and other situations where you have ZERO traction, about the only good it will do is lower the chances of you going into a skid, however it is still possible for a wheel to lock long enough for the car to start to skid, but usually with ABS you have a better chance of maintaining control. ABS or not, increasing the distance between you and the car in front of you more than you normally would, when you know the roads are slick, helps as well.

[SevenSisters]

ABS is not as good as a professional driver that can keep the brakes from locking up during a panic stop. For the rest of us they're great because the stopping power of the pads rubbing on the rotors is greater than tires burning off rubber in a skid or just sliding on a slippery surface. Rain or shine, snow or no snow, ABS is NOT a low traction condition aid. ABS is meant to be mashed to the floor when you have to. DO NOT PUMP ABS in a panic stop! REPEAT: DO NOT PUMP ABS in a panic stop!

 

As for your ABS issue, one time in 14 years of braking the '91 'ru, I had a similar experience. One winter day, as I was leaving work, I backed out of the parking space and no brakes. I did some additional stopping with no issues and drove home. I had no further problems and chalked it up to ice on the rotors or pads. Your post has me thinking that was not the case. Thanks for the post. Unfortunatly, your mechanic may not be able to duplicate the problem, but check on the recall.

[charlierh2]

sadly the fuse that controls the abs also runs the cruise control so youll loose that if you take it out

[Setright]

What kind of tyres is the car wearing? Summer tyres will have very little grip in snow and the ABS is only doing it's duty of preventing wheel lock-up. On Bridgestone Blizzak I find that my ABS braking distance is only marginally longer than without. However, with ABS you still have some influence on where the car goes. Remember to steer around stuff. ABS does not reduce braking distance.

 

NO professional driver can pump four wheels independently like an ABS system.

 

The ABS system Lotus and Delco developed nearly ten years ago is probably the best idea ever. It doesn't pulse the brakes, it controls the line pressure variably. That means reduced stopping distances.

 

 

Ice is the only exception, ABS should be shut off, and the car shod with studded tyres. When these lock up on ice, the provide the shortest stopping distance.