My 97 Subaru Legacy Wagon has this intermittent braking problem. When I start the car in the early morning in the winter (below freezing temps), an initial depress of the brake doesn't work. However, if I let off, then depress again, it catches and then is normal.
It happened last year as well in the cold weather only. Anyone else with this experience?
Change your brake fluid; it's got water in it which is freezing.
I go along with Limey Lurker - start with a flush of the fluid. If that doesn't do it (and especially if you are saying the pedal sinks to the floor the first time) you are looking at master cylinder overhaul or replacement - which can be expensive with ABS. But if the pedal is sinking, don't put off repair. It will soon reach the point where it does that when warm and you want to stop. Master cylinder replacement is always cheaper than an accident
*plus* master cylinder (or car) replacement.Mike
I have noticed the same thing on my '96 Legacy on really cold (single digit) mornings (takes excessive pedal pressure, first couple of applications, then normal?). I seem to notice this particularly if the car had not been allowed to warm up all of the way the time before (corner store/beer run/whatever). I suspect that the check valve in the vacuum booster line is picking up enough moisture to freeze closed (or maybe it's just sluggish in the cold; aren't we all?), hence no vacuum boost until it thaws, or the engine develops enough vacuum to pull it open anyway. At least that theory is consistent with the symptoms. It's been cold and snowy here the last few days. Haven't had the Legacy out, but I'll try it tomorrow AM and see if I can verify that this is what's happening. The check valve is just a little plastic thingie; couldn't possibly cost more'n $1000 or so . . . ;-) I'll scrounge one from the local Soobie yard, work the ol' swapperoonie on it, and let you know what I find, so stay tuned. Meanwhile, just let your car warm up a bit longer before pulling out of the drive, and see if that doesn't alleviate the problem; works for mine.
ByeBye! S. Steve Jernigan KG0MB Laboratory Manager Microelectronics Research University of Colorado (719) 262-3101
I don't think I'd've ever thought of that! I'll sure try not to forget it, though! Thanks!
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