Can a sinus toothache still have sensitivity when tapped?

Yes and no: Toothaches of sinus origin can be tapping tender and cold sensitive. Often times on multiple teeth in the affected area (upper back teeth). Don't forget, however, that an equal possibility is a tooth-centered problem that has nothing to do with the sinus. A skilled general dentist or endodontist can be helpful in determining your case.

Yes: This is a common sign. See if the problem is from tooth origin or sinus origin. Visit your dentist.

Yes: Yes. If tooth pain persist after resolution of sinusitis, see DDS.