Normal ABS behavior. If you're on the brakes almost hard enough for lockup, but
just not quite, they'll pulse lightly, on impending lock. They don't actually
wait for the wheel to stop, but for one wheel to have a significant difference
in
speed compared to the others. If you really stand on the pedal, this happens
faster, and more often, and results in more brake pulsing.
Depends on the surface, too. If you run up to an intersection pretty hard on a
dirt road and stand on the brakes, you'll probably go right through the
intersection as the brakes spend more time off than on. Um, don't ask me how I
know. . . . Dirty asphalt will have your ABS pump whining overtime. Concrete,
of course, rules.
You can find yourself threshold braking into ABS just like you'd threshold brake
into lockup. You here the front end jackhammering, you back off just a tad on
the
pedal, or give it a little pump. The safety nazis tell you to just stand on it,
but you'll stop better if you can stay out of ABS, especially if there's any
looseness to the surface.OTOH, be thankful that your tires don't have all those
round cordy marks on them that other people get.
ABS can throw the car around, too. Imagine trail braking very deep, probably too
deep, and as the inside wheel gets light, the ABS backs off that brake.
Suddenly, momentarily, the car is only braking on one side, and will turn into
the side with brakes, i.e. away from the apex You'll miss the apex for sure,
wider than if you'd slid past it dragging the inside front tire. Again, don't
ask
me how I know.
Walter Fooshee
Dixie Region Probe GT
Mtnman3620@aol.com wrote:
> Hey all,
>
> I was noticing something this weekend at a local autox that really upset me
> and led to something that was rather unexpected--an off-road excursion.
>
> I had noticed when I ran in the rain in my car that the abs came on pretty
> suddenly. Nothing out of the ordinary there. I have noticed lately, though,
> that my abs comes on from almost the time you hit the brakes. Granted, I hit
> them hard but not hard enough to lock them up. Also, when I hit them even
> harder (stand on them), the frequency of the pulsation changes (no, this not
> a warped rotor). Any thoughts?
>
> Just for more info and something that could have a bearing on this--my
> speedometer is off by +5mph with stock rim diameter and stock tires.
>
> Daniel Ledford
> 99 Mitsu Eclipse GSX
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