There is no standard citation style that covers the whole of engineering and each of the disciplines defaults to using the style used by their major professional association for their scholarly journals (e.g. ASME citation style is used by mechanical engineers). IEEE style format is becoming a citation style accepted across all engineering disciplines. Below are guides to these styles (not comprehensive).
CSULB's Style Manual and Citations Methods is a good starting point. The American Psychological Association (APA) citation style is frequently used for Freshmen engineering courses since there is no standard style that covers all of the engineering disciplines.
As you progress in your program, you will use the citation style developed by the appropriate professional association for your discipline (e.g. mechanical engineers use the ASME citation style).
Please also see our guide to Plagiarism
For Honors and Masters Theses, discuss with your Advisor the style that they would like you to use.