No Subject

["Al Powell" <APOWELL@agcom.tamu.edu>]

"McIntyre, Richard" <mcintyre@wsbs-mses.eng.pko.dec.com> said:

...the noise is not really speed sensitive.
> It NEVER occurs while coasting or under significant acceleration.  It
> ONLY occurs when the accelerator is very slightly "open" -- at the 
> point that speed is just maintained.  To me this means it's 
> related to either 1) intake vacuum, or 2 torque somewhere in the 
> drive train.  There are certain speeds at which the noise is more 
> noticeable.

The vacuum issue is a possibility. Remember that you have maximum 
vacuum when you let up on the throttle - accelerating reduces the 
amount of vacuum present.  Most vac. leaks happen when you have more 
vac - which would mean deceleration.  So this noise is indeed 
different, in more than one way.

> My car has no speakers in the dash, yet the sound source seems to be
> located in or in front of the dash.

Kinda rules that one out, dunnit????

> I guess maybe you have to experience it to understand why we
> think it has nothing to do with the radio or speakers.  It 
> is certainly perplexing.

I understand that now!

You still may need a passenger with a sharp ear to go all around that 
dash while driving - maybe with some of the under-dash panels removed 
to let the noise out more clearly.  

I think vacuum is more likely than torque, as you otherwise would not 
be hearing it from the dash....
Al Powell                           Voice:  409/845-2807
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