While their engines functioned, they could be controlled after a fashion.

Our engines are not functioning as we expected.

Failing that, we may be able to give you a tow to an area of space where your engines will function better.

"You're aware that your engine can't function without fuel?"

"What will you tell them when they discover our engines are functioning?"

However, the engines are no longer functioning normally and the satellite was sent on a direct collision course to planet Earth.

"The engines are not yet functioning," C put in.

But the lights were soon on, and Rice's engine functioning again.

"The engines are presently functioning at one hundred seven percent of normal capacity."

Even with the lower-than-normal plasma levels, Scott was confident that the engines would function adequately enough to get them home.