If you have a visa-exempt passport, it should not be a problem.
If you don't have a visa-exempt passport, you can still use your passport+COPR to cross at a land border using non-commercial transportation (private car, walk across, etc)
By your previous posts, I assume you hold a Philippines passport?
If you are driving across the border by private car, there is no problem. As Keesio said you can just use passport+COPR at the border when you drive back to Canada.
However if you are flying, that is a problem. You will not be allowed boarding in New York without an actual PR card. They will not accept your COPR to travel by airplane or even coach bus.
So with no PR card, you will need to arrange to get a travel document from New York in advance. You can see how to do that here: http://www.cic.gc.ca/english/information/applications/travel.asp
Remember you may also need an American visa to visit the USA. I'm not sure the requirements in your case.