It seems as if my ABS has been prematurely kicking in during otherwise routing braking situations. I am a bit concerned about this and am looking to see if anyone else has experienced this before. I must emphasize that I am NOT driving agressively enough to warrant ABS engagement. Furthermore, I have modified the braking system a bit which may be relevant to the topic at hand -

1) SS Brake Lines
2) Drilles/Slotted/Cad Plated OEM Rotors
3) DOT 4 "Super Blue" Fluid
4) Porterfield R4S pads (very light wear)

I have experienced ABS engagement during the following scenarios -

1) Light-to-moderate braking over uneven (e.g. "rippled") roadways. This is where I first noticed it occuring.
2) Moderate-to-hard braking on dry, smooth roadways. Pedal not even close to being pushed all the way.
3) VERY easy to engage ABS during wet-weather conditions; again, light-to-moderate braking.
4) Does not matter if braking in straight line vs. corner
5) Even after I've "warmed" up the pads during an extended drive I experience the same thing.


I would also add that a few months back (with identical brake system setup) during Fall Colors '02 I never experienced this at all, even with "vigorous" braking. I am trying to determine the casuality of this. Much colder weather in the Washington, DC area lately? Pads not adequately warmed up? It hasn't been that cold in the area; never below 20 degrees or so. Car is parked inside so there isn't any ice or moisture buildup on rotors.

Help! Thanks in advance for your suggestions.

 

Are you running stock tire sizes? Wrong tire sizes can confuse the control unit and activate the ABS. An air gap to large on a wheel speed sensor can also cause early activation, But will most likely illuminate the ABS light as well.

 

You still have the stock rotors? If so swap them back and see if problem is gone .... my guess is this although I don't agree with every aspect of the article.

 

Remove the ABS motor fuse and try to get some wheel lock up with the same pedal pressure. This should tell you if the problem is ABS related or something else. With the fuse out you will see the ABS failure light on the dashboard. This light will go out when you reinstall the fuse (remove and reinstall only with the ignition turned off!).

 

Another consideration: You say your outside temps have been dropping. Have you kept track of your tire pressures? Cold temps can cause pressures to drop but more importantly, they can cause a tire that has a weak bead or some other abnormality to lose air faster than another tire. If you have uneven tire pressures, this, combined with those other factors you mentioned may play havoc with the ABS.

 

[QUOTE]Originally posted by Hiroprotaganist
[B]I have experienced ABS engagement during the following scenarios -

1) Light-to-moderate braking over uneven (e.g. "rippled") roadways.

 

Thank you all for the suggestions. Some further information.

1) Am running OEM wheels/tires
2) Shocks are great all-around. Car has about 20k miles on it and I don't beat it.
3) I have NOT checked my tire pressure lately. I will do that this evening. While that may be a contributing factor, I don't think it is the primary cause.
4) All tires are in great shape with plenty of thread.

I will pull the ABS fuse tonight and see what happens. While swapping rotors might certainly help out (thanks for thinking of that), I want to avoid the time/expense of doing that right now because I know they were working properly before with these rotors. It is true that I have made the braking system more powerful, but the fact that the ABS engages during light braking indicates to me that there is something else amiss!

Any other suggestions would be more than welcome! Thank you all!

 

Washington DC + S02s + December = traction problems

Are you sure it's not the S02s loosing grip? No matter how much tread they have left, once the temperatures drop these tires don't grip any more. Most S2k owners up here in New England have already either stored away their cars for the winter or switched to winter tires.

 

Wow - I guess I never realized it could be a temperature-driven issue. Would this be proper logic?

colder weather + S02s + upgraded braking system = higher probability of ABS engagement.

In and of itself, does this seem to be plausible? I'm not suggesting that it isn't, just wondering what the consensus is.

 

[QUOTE]Originally posted by Hiroprotaganist
[B]colder weather + S02s + upgraded braking system = higher probability of ABS engagement.

In and of itself, does this seem to be plausible?