[burly]

First off, you don't want to trick any sensor on the engine, as it can cause all sorts of problems. This can result in not only poor mileage and possible Loss in performance, but it could also damage your engine.

As for the intake, there are several options out there. I have been told that cold air intakes for the 3.4L V6 put in the grand am and alero, will work on the 3.1L V6. Doctor Speed sells several intakes, including a cold air version.

http://www.doctorspeed.com/products/cai/index.html

FDP Performances also makes one, their site is under going a rebuild, but here is what is currently up:

http://www3.sympatico.ca/fjpeters/

And RSM Racing has an intake, though it is not cold air:

http://www.rsmracing.com/us/main.htm

I think some of the other guys in here have actually installed intakes on their malibu's and hopefully they can chime in with their thoughts. I have a 2003 that I want to put an intake on myself, but haven't had time yet.

Hope this helps!