That was my problem and the new oil sending unit from autozone for 31 dollars fixed my problem. good luck

Hi I just bought a 01 pontiac Bonneville SSEi and I am excited about it here is some pics of it.

http://dallas.craigslist.org/dal/ctd/1507377826.html

My drivers side air is cold when I turn on the heat. The passenger side is hot but the drivers side is cool even on 90. What could be causing this and how to fix it.