Difference between present and past simple after 'suggested that'

These are the sentences that I found in Cambridge grammar books:

I suggested that she bought a car.
I suggested that he gives up golf.

Both of the sentences above start in the past simple but end in the past simple and present simple respectively. Why is that and what's the difference in meaning?

UPDATE: Now that I'm thinking about it, I have a guess about the differences between these two:

"I suggested that she bought a car" means:

I suggested that she bought a car but at the moment it's not clear whether she has bought it.

"I suggested that he gives up golf" means:

I suggested that he gives up golf but he hasn't given up it yet. Perhaps later. Or never.

Though I'm not sure about it and need someone to confirm.