exhaust/gas smell in interior or... what's all this flap about a heater flap?

["Tom Borden" <te.borden@xxxxxxxxxxx>]

Hey all.
 
Replaced my heater control valve eight weeks ago.  Car gets nice and
toasty, but. over last four weeks or so, seems like there's smell of
exhaust/gas coming into the car.  This doesn't happen all the time, but
perhaps 50% of the time.  I do not believe this is from a leaky gas tank
(which I once had) as that would leave gas smell outside of car at rear
as well - and besides, sometimes this smells like exhaust.
 
I seem to recall someone discussing "flaps" that control air flow into
car.  Would my 1988 52e have a flap or flaps?  Would anyone know where I
would begin burrowing to inspect/fix?  Or should I suspect component in
engine compartment for gas smell?
 
Lightheadedly yours,
 
Tom
 
THOMAS BORDEN  |  CONSULTANT | MEDIA & MARKETING COMMUNICATIONS
23 ESSEX ROAD, ESSEX FELLS, NJ   07021 | ph/fax: 973.228.5092  |
<mailto:teborden@domain.elided> te.borden@domain.elided

------------------------------