I have a 1996 960 with 202k miles and lately, I've noticed a bad exhaust smell whenever the car is standing still. I thought maybe it was just sucking in exhaust from the cars in front of me at the red light, but I smell it even when I'm stopped all by myself. During the winter now, when I start the car to warm it up, it's almost unbearable when I get in it after it having sat idling for several minutes. Could it be an exhaust leak somewhere? Where would I start looking?

Thanks!