Is the check engine light on?
BTW, the purge flow sensor, and a good bit of the hose connections are tucked in behind the passenger headlight. A little tricky to access.
On Brenda's old 96 Cougar, replacing the purge flow sensor fixed the problem, at least for several years. Then the CE light came on for the same thing for a couple months, then went back off! That is one flaky system, on all cars.
Sorry to hear you have to have an OBDI car smogged. Most states just have visual for 95 and older.
97 T-Bird LX 4.6 - 80k miles
94 Supra TT Auto - street/strip car
04 CVPI- Brenda's car - 76k miles
95 T-Bird LX 4.6 - fully optioned, owned 15 years, 220k miles
96 Cougar XR-7 4.6- Brenda's car, owned 11 years, 187k miles
88 T-Bird 3.8 - first T-Bird, owned 5 years, 206k miles