Here's how to find a leak
Make a plywood hatch board
Seal up all your air vents by stuffing in rags, etc.
Get a shop vac.
Put the hose on the exhaust side
Measure the hose fitting diameter
Cut a hole this size in your plywood hatch board
Mix up a solution of dish soap & water in a pail.
Shove the hose into your hatch board, duct tape it in place
Turn on the shop vac
Soap up the deck, and look for bubbles.
You'll find it!