#6 not firing!

The hose in question is meant to go to your evaporative emissions canister. It collects vapors from the fuel bowl and stores them until you chop the throttle and the high vacuum draws the vapors into the intake manifold. Over the years they get full of crud and allow high vacuum to show up at the fuel bowl vent. When that happens, all the fuel is sucked out of the bowl and the car runs like crap. You can either replace the canister or leave the bowl vent open. This affliction was foisted on us in 1971. Good luck finding a new canister after 27 years.