Re: ABS Screwed?

[johnholt@cybernet.on.ca (John Holt)]

>Andrew Duane USG/PE wrote:
>>
>> Hairy green toads from Mars made Sean Douglas say:
>>
>> > Every morning when I back out of my garage, I get this humming sound for
>> > about 2 seconds and the pedal goes soft, and it feels like the ABS is
>> > interfering. It also happens very rarely in traffic when coasting slowly
>> > up to a stop sign or light.
>>
>> Sounds like a dead/dying ABS sensor or loose/cracked wire
>> to one of the sensors.

Chris wrote....

>I'm not so sure. I believe that the ABS does a self-test the first time
>your speed exceeds ~5 MPH after a power cycle.
>
>I've also seen the occasional "reset" occur once I move off following
>a hard stop (though not hard enough to engage ABS). Dunno why it does
>this though.
>
>All of this on a '93 90... FWIW

Chris...

Andrew diagnosed a similar problem for my 1988 90Q. The proof was that when
I turned ABS off with the dash switch, the problem disappeared. Would
suggest that BEFORE you back up, push ABS off and see if the humming and
ABS cycle recurs. If it doesn't, you have isolated the problem to ABS and
probable sensor mis-alignment.

John

2 of those 1988 90Qs