Valet
IS300 SX > Accord
I like the smell of paint.
I think it might be the thing behind the dash.... You know, where the heater core is, but the thing for the a/c..... Whats that called? That thing lol. I think theres a leak there because its not in the engine bay, its only through the vents.
Evaporator Core.
And. Whatever you do, Don't DIY this. I've done it on a saturn, It was in pieces, baggies and parts for a week. Over 200 Screws and seats, carpet, entire DASH down to the firewall. However, might be easy to do on the Accord.
Check Chiltons first.