Bought / Buy

[jack]

Are these correct? Do I use 'buy' or 'bought' ?
1. If this car is not performing the same as the first day you bought it later on, we'll fix it for you. (If this is okay, why? 'Bought' doesn't match with the other tenses? )
2. If this car is not performing the same as the first day you buy it later on, we'll fix it for you. (This one sounds awkward with 'buy'?)

What about these ones?
3. If later on you notice that you car is not performing the same as the first day you bought it, we'll fix it for you.
4. If later on you notice that you car is not performing the same as the first day you buy it, we'll fix it for you.
Thanks.

[Alc112]

Are these correct? Do I use 'buy' or 'bought' ?
1. If this car is not performing the same as the first day you bought it later on, we'll fix it for you. (If this is okay, why? 'Bought' doesn't match with the other tenses? )
2. If this car is not performing the same as the first day you buy it later on, we'll fix it for you. (This one sounds awkward with 'buy'?)

Thanks.

Because if you are speaking in present you have to end speaking in present

In yo examples you put "You bought it later on"
I think that Later is saying something for the future so past dont look well there.

[Tdol]

I'd use bought in these examples.

[jack]

I'd use bought in these examples.

Why is that?

3. If later on you notice that you car is not performing the same as the first day you bought it, we'll fix it for you. (I know the tenses don't match , is it because I'm talking about different times here?)
4. If later on you notice that you car is not performing the same as the first day you buy it, we'll fix it for you. (It is talking about when you buy it later and performing later? So is that why it doesn't make sense?)

[Tdol]

The day you buy it = future
The day you bought it = past
Even when we're thinking about problems in the future, they will be after the purchase. The puchase may be future, but it will be past when you notice the problems.