no oil pressure

2002 Cavalier ecotech 2.2. I have no oil pressure after changing balance chain and sprocket.

Are you physically able to tell there is no oil pressure or is your sensor telling you that?

The sensor is telling me so.

Disconnect the power to the coil so it won't start. Put a pressure gage in the system and make sure you don't have any pressure. If you don't have pressure I would go over your work to check everything was hooked up correctly. If you had no pressure before you started pull the pan and check for a plugged strainer. Look at the oil pressure sending unit and make sure it is plugged in first. Look at your manual and for any left over parts,that would drive the oil pump. If everything worked fine before starting it must have been something you did incorrectly.