Volvo Repair: 95 Volvo 850 - Fume smell in cabin, volvo 850, exhaust fumes

Question
Everytime I run the AC, a faint yet significant exhaust smell comes out of the vents. It's tolerable on short hauls, but on longer trips it becomes unbearable. When at idle or stop lights, the fume smell becomes more pronounced. I can fix the problem, just need someone to help me diagnose the problem. Thanks for any insight.

Answer
Are you sure its exhaust fumes? Is your exhaust in good shape? Many times I hear of this complaint and it is oil leaking onto the exhaust. Is it a turbo? Is a check engine light on? Are you running the AC with the recirc on?These are all things I could check in seconds in person, but I have to ask in this forum.