[Shotimes] Speedo and ETAC

[David P]

You gave the answer in your last sentence. One of the uses of the IAB is to
compensate for the drag of the a/c compressor. When the heat comes on, and
subsequently the compressor (to remove excess moisture from the cabin in
winter), the IAB opens up a bit. Without a compressor, you are going to feel
that compensation as surging. I suppose you've noticed this surging does not
occur at half throttle or above...

I've always identified a solid, high-frequency chirp as the blower motor
bearing problem. Don't get all excited about it unless you've got a really
bad chirp. Replacements seem to start making the same noise before too long.
I combated the problem by putting on higher performance tires, Eibachs and
Konis. I am an equal-opportunity noise absorber, and it seems the rest of
the car has dutifully stepped up to the plate now.


David P

95MTX



~
----- Original Message -----
From: "van Oss" <vanOss@centurytel.net>
To: <shotimes@autox.team.net>
Sent: Sunday, January 19, 2003 10:40
Subject: [Shotimes] Speedo and ETAC


> A few weeks back, I reported a chirping sound behind the dash.  Yesterday
I replaced the upper speedo cable (lubed both) and the
> chirp is still there.  So next I am going with Kevin Airth's
recommendation to swap the blower motor.
>
> While investigating the chirp, I've been driving around while turning the
ETAC on and off.  I've noticed that at steady throttle,
> the car definitely surges forward a bit when the ETAC is turned on.  Any
guesses on why?  BTW, the entire AC system has been
> removed.