[V8] Bomb question, update

Kneale Brownson knotnook at traverse.com
Mon Sep 13 07:46:51 EDT 2004

"Bombs" don't "build back up".  The red light on start-up after the engine
not running for quite some time is the power steering/brake pump
repressurizing the system because the accumulator isn't doing its job
anymore.  The "bomb" has a flexible diaphragm that holds something like
2400 PSI of a gas.  The power steering/brake pump supplies its hydraulic
fluid against that diaphragm and valves keep the pressure up.  Over time,
the diaphragm leaks some of the gas and there is less pressure behind it.
So when the pump isn't running, the pressure drops in the accumulator.
That means when you start the car, the red light comes on for lack of
adequate pressure.  Eventually most of the gas apparently escapes through
the diaphragm and the "bomb" basically doesn't work at all.

At 11:00 PM 9/12/2004 -0400, QuickAudi at aol.com wrote:
>I was going to point out a few more things.  One, my brake light would come 
>on when I started the car, stay on for ten to fifteen seconds, then go off.  
>If I drove the car and shut it off, then turned it back on, the light would 
>not repeat the staying on part.  However, at the end of my work day, it 
>would sometimes come on and stay on for the ten or so seconds.  
>At any rate, put on a new bomb (thanks Blau!) yesterday.  I have had great 
>pedal response and no problems with panic stops, even in rain.  I'll let you 
>know if that changes in a week, which is did after my last post of 
>"repressurizing" my bomb (aka, I pumped the brakes and allowed it to build 
>back up for a while.)

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