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Re: ABS? Brake Posted by Ari [Email]  (#2847) [Profile/Gallery]
(more from Ari) on Sun, 16 Nov 2008 20:23:52
In Reply to: ABS? Brake, Rick, Sun, 16 Nov 2008 19:43:27 Members do not see ads below this line. - Help Keep This Site Online - Signup |
The giveaway was "and the ABS and brake lights stay on after starting" You've got no (or insufficient) brake boost. You've got a car without power brake assist. This isn't like the old days of non-power brakes, the braking (as you know) is much worse.
The brake boost uses the same pressure source as the ABS. When the car is first started, the ABS pump should run. It pumps fluid from the brake fluid reservoir and into the accumulator. The accumulator stores the pressure which is used for both brake boost and ABS.
If the pressure is too low, you get both the ABS and the Brake Fluid lights on. You should hope it is the accumulator - it's easy and relatively cheap to fix. A bad ABS pump is very expensive.
Start with the easy stuff. When the car has been off for a while, where is the Brake Fluid level in the reservoir? It should be ABOVE the full line. Start the car. You should hear the ABS pump run (buzz) and the brake fluid level should drop. Ideally, it drops down to the FULL line.
If you start the car after it has been off for a while (hours), and you don't hear the ABS pump run and the brake fluid level doesn't drop, first check all the ABS fuses, including the big 30 amp ABS pump fuse. If the fuses are all good, but the pump isn't running, it might be a bad pressure switch. But most likely a bad pump.
If you hear the pump run and the level does drop, but only a little, it might be the accumulator. But I doubt it. Even with a bad accumulator, the system will reach pressure and the ABS and Brake Fluid lights will go out. You'll have little or no boost (depending on how bad the accumulator is), but the lights should go out.
If the pump is running, let the car sit for a minute or two - does the pump stop? Do the lights go out? If the pump doesn't stop running, you've got a bad valve in the ABS system - the valve is leaking, and instead of the ABS pump pressurizing the system, it's just swirling fluid around the system through the bad valve. The ABS pump won't last long at that rate.
AND if you've got no fluid in the system because it got too low, refill and flush the system, as it has air in it.
posted by 76.200.21...
, Mon, 17 Nov 2008 21:00:07, Mon, 17 Nov 2008 06:46:53, Sun, 16 Nov 2008 20:23:52 <-- Viewing This Message
, Sun, 16 Nov 2008 22:29:04
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