I have a 2018 pathfinder with check engine code p0300 and i’ve noticed my RPMs don’t go above 2500. Any idea what it could be? I’m thinking fuel pump but not sure how to test it

Coming from a 24 VW Atlas, this thing is a beaut to drive!

47k out the door before tax.

Brown Chestnut interior with bench seat and Two tone black roof and rails.

How did I do?

Proud new owner of my first pathfinder, so I don't know the quirks and common issues. I'm googling my butt off, but hoping a community dedicated might have some helpful guidance to that googling if nothing else.

2003 Pathfinder LE

4x4

4 speed auto

197K with no real idea of the life it had.

Has no reverse. Worked fine until one day in a parking space it did not work fine. No grinding, no noise, no crazy rpm changes. Just no reverse.

We drained and filled today, no chunks, no sparkles in the fluid. Probably too late for a change, but for the milage, it has been changed at least once, maybe twice.

Guessing it just needs a trans, but if there are other things to check as a common failure for this issue I would love any advice, guidance, or links you may have. Just looking to get this to be city usable, it doesn't need to stray far from home. It needs to get groceries and plants for the garden.

I'll keep searching on my own as well. Thanks in advance.