Sugar causes the body to produce more fat and oil. Oil clogs the pores in the skin and that leads to pimples or acne. So yes it does.
You would be so amazed at what drinking lots of water would do, not just for your skin, but for your entire body. Try cutting back to just one soda, or none if you can stand it, a day and increase your water intake as much as you can. You won't see results over night but should within 2 or 3 weeks.
I used to think that sugar causes pimples and would very seldom eat sweets or drink sweet sodas etc. However about a year ago I read in Oprah Magazine and some other sources that the fact that sugar causes breakouts is one of the beauty myths! They say that actually sushi causes you pimples due to iodine - I don't know what to believe anymore! However sugar does other bad stuff to your skin - it starts a process called glycation which damages your skin's collagen.