Dropping calculus in my second semester senior year, how will it affect me?

I currently am holding a very low C grade in my AP Calculus AB class in my second semester year of high school. In the first semester, I barely scraped by with enough to have B in the class, but this semester has been horrible. I wouldn't say I have a case of senioritis, in fact, I've been working harder than ever before, completing all the reviews and assignments, but I just can't pull it off in the test. 
I am already admitted to many UC's and the two Cal State's I applied to for mechanical or computer engineering. I know if I audit the class it would not appear on my transcript but I would have to report the change to the admissions office of the schools I am admitted for. I have already signed my intent to register with UC Irvine for mechanical engineering, but I am afraid to audit the class due to the fact that they can rescind their decision. I know it looks bad that I am dropping a math class while going into a STEM major. 
 And with the covid-19 quarantine, it is just going to make it all the more difficult for me to pass the class. I am worried about getting my admission rescinded if I drop the class, but I'm at a huge risk of failing the class and possibly getting rescinded anyways. 
Any Ideas? If I drop Calculus AB after admission into UCI for mechanical engineering, will that affect me? Would they care and revoke my admission if I drop due to a failing grade even though I completed the minimum required amount of math classes for admission?

Either a drop or a D/F grade in a course that you reported as in-progress on your application risks rescission.

You should ask UCI (and other colleges that have admitted you already) whether that will actually result in rescission in your case. Better to find out now than to surprise them in the summer, which they will not like.