I seem to remember the barometric pressure sensor costing in the neighborhood of $150.00, and it takes all of about...hmmm...5 minutes, tops. This sensor also plays into the climate control system, so therefore, it can affect your air conditioning. Now that it's about to be October that is most likely less of a concern. If funds are super tight, keep checking your codes so that you are aware of new ones should they occur. (I hear AutoZone reads them for free). If you can spring for the part, do it yourself. It sits sorta on the inside of the passenger side fender, right up top, right up front.

Hope this helps,

Chris