1.
If an engine is ticking over, it is running at a low speed or rate, for example when it is switched on but you are not actually using it. (BRIT)
Very slowly he moved forward, the engine ticking over.
= idle
PHRASAL VERB: V P
2.
If a person, system, or business is ticking over, they are working steadily, but not producing very much or making much progress. (BRIT)
The market is at least ticking over...
PHRASAL VERB: V P