Hyundai: 1998 Accent Problems

I took my '98 Accent to Autozone to have the check engine light checked.
These are the codes that came up:

P0447 - "The PCM has determined that a open circuit condition exists in
the electrical circuit for the vent control in the evaporative emission
control system." A friend of mine that's familiar with cars told me it
was the gas cap and not to worry about it. Another told me it might be a
hose that's leaking/torn.

P0733 - "The PCM has detected an incorrect gear ratio condition in 3rd
gear."

P0717 - "The PCM has determined that there is no input voltage signal
from the turbine speed sensor."

P0722 - "The PCM has determined that there is no voltage signal from the
output speed sensor."

One code didn't have an explaination - P1614.

Does anyone know anything about these codes? I would REALLY appreciate
anything you can tell me.

Thanks.

At my dealership, rough estimate for the pulse generators would be
$200-250. We're in a high rent district, so unless you're in New York or
LA, expect less. The P0447 will require some diagnostic work, so the cost
to repair will depend on how long it takes to trace and locate the
electrical problem and exactly what is required to repair it.