Conversation Between Truckin Bob and JenniSAnanna

Hello Truckin Bob,

I am thinking about buying a 1988 E150 econoline van, to move from Kentucky to Colorado. My son-inlaw starts Kemo soon.. I am I Love with the Idea of reliving my Youth..Putting long shag carpet inside,TV, XBox, bed and disco ball. Cranking up the 8 track and painting dragons on the side...having a place for me or son-in law to go hide when needed..
My issue is.....
The present owner says it has exhaust leak somewhere and not a lot of power..
The leak seams to be coming from behind the passenger seat.
So my limited knowledge. exhaust manifold problem? Catalytic converter? Muffler-which the owner says no. That the problem"" goes away with the heater on or cracking the window?
I am stumped...
Any Ideas how to tell what's what?

Thank You
Jenni