1) The person "comes on too strong" in a general sense, that is, he tends to be overbearing. The Spanish for this might be:
Intenta dominar la situación (o la conversación).
2) The most probable context is where a man "comes on too strong" to a woman, that is, he tends to force himself on her. In colloquial Mexican Spanish, you could say:
Le echa (o me echa) muy fuerte los canes.
If it were from a female to a man....Me da demasiado jalón.