Help! Failed CA smog test: Fuel Evap Controls Functional

[turbo110]

My '95TT just failed the Fuel Evaporative Controls Functional (it passed the other FEC, whatever that is). Everything else passed (the HC by a super-slim margin). I was told I needed to get the fuel system "smoked" to determine where the leak is; the mechanic I've used a few times says this will be $140 just for the diagnostic, and he's not sure whether the replacement parts are going to be available.

If anyone has any experience or advice on any aspect of this, I'd love to hear from you! I'm pretty broke and feeling a tad freaked out about what this could cost. I just learned that there might be financial assistance available for repairs, so am looking into it. I've also read some sinister postings about STAR stations being rewarded for failing older cars, but I'm trying not to think about that! Many thanks...