Impreza exhaust / cabin leak

[cobs]

Seems to be my week.

Got a '96 Impreza HX, and apart from wind noise sparking up, I'm getting
what smells like whifs of exhanust fumes through the vents at slow speeds.

I don't get anything over ~80k, or when the air is on recirculate.

I've got a service coming up - is there anything I can look at in the
meantime?
(Summer at the moment, the windows are down most of the time.)


Thanks

Cobs