Originally posted by 99SESPORT:
You don't need to post two times...Just hit the REPLY button at the top...

Or edit - but whatever, let's talk about the car...
Originally posted by Ferret II:
We popped the lid at home and found
there's an obvious wheeze every time we throttled up, audible by the throttle and also back by the driver's (or passenger's) doors. We couldn't see anything wrong, but suspect maybe fuel pump or filter (thought vacuum leak at first but now my husband is doubting this).

I'd bet that this is actually the (or a major part of) the problem. IIRC, some (or all) of the vacuum lines have a tendency to become brittle and crack.
Originally posted by Ferret II:
Filter was supposed to have been changed about 10K ago, but Janos (husband) looked at it and
said it looks like maybe it wasn't.

I doubt it's causing the problem, but change it anyway - cheap and quick.
Originally posted by Ferret II:
The weirdest thing was that fuel guage fluctuation. I've never seen anything like it!

Me either...

2000 Mystique LS Duratec 2.5L MTX