[V8] bad bomb, master cylinder or ?

[Tony and Lillie]

You still have an ABS issue. That's what is causing the pedal effect. Also, 
you should check the clearances and teeth. Basically, it sounds like one of 
your sensors is not working properly. If you have access to an O-scope, you 
can also watch the output as you spin each wheel. But, I'd start by simply 
pulling and cleaning them.

As a side note, a friend went a year witt the diff locking/no ABS. We found 
the problem (worn through wires on a front sensor) and his system has been 
troublefree since. That was at least five years ago. Mine has been 
troublefree ever since purchase 6 years and 80K ago. Can't say the same for 
the rest of the car, though.

The reason I'm telling you this is perhaps it will help keep the motivation 
there for you. I know all too well how easy it is to give up on a problem.

On a side note, Seamus' situation does sound like either the master cylinder 
or a broken line somewhere. Check for fluid leaks all around the car first 
after pushing on the brakes several times, letting it leak out to leave a 
good trail if that's what is going on.

Tony


Subject: Re: [V8] bad bomb, master cylinder or ?


>I have the exact same symptoms you describe with the brake being hard at 
>the top of the pedal and then sinking down 2 inches before it engages.
> It happens usually after the car is first started and for the first couple 
> of brake pushes.
> I replaced the master cylinder, and it had no affect whatsoever!!
> It almost appears to be ABS related, because I think I can hear the ABS 
> engaging with that grinding pulsing noise very, very slightly on the first 
> trip down my driveway in the morning.
> My bomb was replaced about 12,000 miles ago.
>
> I also have the differential locking up at slow speed issue, with the 
> 'ABS-Off' light coming on sporadically.  I have replaced one ABS sensor, 
> (the one with the higher resistance, with also absolutely no affect.
>
> Maybe if I replace the whole car, it will have an affect!!!  :)
>
> mark.
>