I'm upset that my dad got my car fixed
What about your dad getting your car fixed makes you upset?
I'm pissed off because that fucker didn't want to listen to me that I complained there was a rattle for a really long time. He didn't believe me until now.
You should appreciate what your dad has done for you, and when you thank him, make sure he knows how you feel about him going over your head. Talk to him about what it has done to you so you can move the relationship forward.
You know what, I'll do that.
While it is nice that your dad fixed your car, it is understandable why you are upset. Just really try your best to demonstrate your appreciation while also voicing your opinions and emotions.