throttle body question

[thoroughbred3.0]

i have a 90 na and im to the whole z thing, actually im new to the whole car thing. when i rev it, only one of the throttle body cable connectors opens. if i rev it from under the hood the left cable wont go in. what is the cause of this and what else will it effect. (there are a few things wrong with the car, including cyl.5 not firing, so its hard to tell what affects what)

[GAZ32]

That's your cruise control cable. No big deal, but not firing in your 5th cylinder is. I'd get it checked out definitely, could be an injector or a coil gone bad. Take it to a somebody who is familiar with Z cars, not a dealer because most likely they'll tell you you need a new engine or something ridiculous.