Wierd ABS shuttering... SOLVED!!!

[harrymaneuvers]

Ok so about a week ago I was driving normal at about 50 mph. When I started my deceleration my 4eat transmission stepped down from 4th to third. Once I got down to about 15mph it felt like my ABS was grabbing... but the repetition slowed as i reached a stop... in perfect balance with speed... after about three more minutes, my ABS light came on and no more ABS pulsing/grinding. When I ran the codes for the ABS, I got (in this order) 41 ( Faulty ABS control module), 24 (FL wheel sensor when no open circuit or speed signal input) and 56 (Wrong control module used or faulty G Sensor)!!!!! Every time i turn the car off then back on... the abs light is off and my 10mph-0mph stops are Pulsing so bad that it almost jerks my car to a stop (very audible)... Also, it seems to go away after i slow to a CREEP. Even if i go 40 feet at 1mph with my foot on the break... there is no pulsing or scraping even with the abs light off?!?!?!?!? I read on another post on here that it is a frozen caliper but then how does that explain the problem going away when the ABS is deactivated. Also its not like my rotors are glowing or anything. All help is appreciated.

Thanks in advance, Harry Maneuvers 1999 Subaru Legacy Sedan 30th Anniversary Edition 2.2L 188k http://farm4.static.flickr.com/3567/348 ... a0.jpg?v=0 (http://farm4.static.flickr.com/3567/3489361826_e0f29f96a0.jpg?v=0)

[Huffer]

If your caliper is frozen then the ABS will malfunction as it's a simple hydraulic system.

If your ABS module has gone bad, or the ABS sensor is acting up, then you will have issues.

Easiest solution to see if it's a frozen caliper or the ABS system is to remove the ABS relay. This effectively disengages the ABS system from your brakes. Now, if you get any major shuddering when you brake, you can start looking at physical hardware.

[jey]

I would replace your FL wheel sensor first. When my wheel sensor went out the system exhibited your exact symptoms, and it was fixed with replacing the sensor.

[harrymaneuvers]

Do you know which codes were tripping your abs light??? was it just the FL sensor code or did you have the faulty ABS module code too??? Autozone wants $169 for a SINGLE wheel sensor. The Subaru dismatler only wants $25 for a used one and $35 for a used one with a 3 year parts AND LABOR warranty. Guess which one I'm gonna go with. pulling the relay wouldnt do me much good because I already know that when the ABS light is on (ABS turned off) it functions fine. Thanks for the help... I am taking to BrakeMasters tomorrow for a free diagnostic... lets see if they are as smart as we are.


Thanks for the help everyone!!!

[decke48]

check over the exciter ring and air gap of the sensor.

[harrymaneuvers]

I have wanted to follow up on this post of mine for a while... it wasnt the abs sensor.

When I had my brakes done last year... the guy informed me that a large section of my ABS tone wheel was missing. The tone wheel bolts up to the inside of the hub. Rather than buying a new one and pressing out the old bearing and pressing new ones in... I got a used steering knuckle from the subaru dismantler here by sacramento and swapped them out.

This fixed my problem 100%.

And FWIT, I drove around without abs or cruise control (fuse pulled) for almost 8 months before I had a chance to swap out the steering knuckle, with 0 problems.

[98outbackpdx]

next time, if you have the same problem put/keep the abs/CC fuse in, and unplug the ABS computer under the hood, you will still have CC but no ABS (at least that is the way it works in my 98 outback.)

[harrymaneuvers]

Not that I need to know anymore... but where under the hood is it??

[Sarra]

Not that I need to know anymore... but where under the hood is it??

Just find the ABS pump, and unplug the harness from it.

[98outbackpdx]

mine is under the air intake the plastic part where the air is sucked in at and it is a pain to get unplugged