Can sudden excessive weight gain 30 lbs cause acne issues effecting all of body? For the first time it's not just my face. Losing the weight now.

Yes. Please do your best to lose that weight. It scrambles your hormones. However, you should be able to address your acne with your physician's guidance while you are getting your health back otherwise. Acne may respond to the oral contraceptive pill or to a mix of antibiotic and topical agent such as benzoyl peroxide.