Get a code reader.,..
Several years ago I bought a code reader and carry it in my glove box. A few weeks ago, 2 hours into an 11 hour drive my truck went into low power mode. Pulled off the interstate at the next exit, checked everything under the hood, and plugged in the code reader. It was a sensor for the turbo stuck in high. I reset the code, check engine light went off and made it home with no more issues. Next day went to dealer and they reported everything was good. Hard to imagine what I would have gone through without the code reader. I bought mine on Amazon for around $50 if I remember right.