Maybe you should do the research yourself before taking a position. It is not hard. 
But here is one source: https://www.washingtonpost.com/blogs/govbeat/wp/2014/03/26/historians-take-note-what-america-looked-like-before-obamacare/?utm_term=.7705d4f9cde7
From the Common Wealth fund report: 79 million AMERICANS either lacked health insurance or were under insured before ACA. That is one in four AMERICANS. 
America, one of the richest countries in the world, cannot provide adequate health insurance for one in four of its citizens. That, to me is what was wrong with health care before ACA. Yeah ACA is not perfect, but it is the first step in the right direction.