2008 Nissan Sentra Loses Power

My girlfriend has a 2008 Nissan Sentra that loses power on the drive to Laramie, WY. We live at about 4,000 feet and hit about 8,000 feet on the drive. It only happens when we’re driving into Laramie. Speeds drop to about 45 to 50 MPH max. It has happened on three different routes into Laramie but has never occurred on the way back out. We’ve tried stopping in Cheyenne and letting the car cool down before starting the climb and it has not had an impact.

Air thins out and engine looses power in higher altitudes. The computer should compensate for the change in altitude, but it can not compensate for a dirty air filter.

Air filter was replaced after it happened the first time. Also it only happens on way IN to Laramie. On way home it always does fine.

Any Check Engine Light or codes present? Temperature gauge pegging out?

Is the altimeter broken?

Check engine light is on but when we pulled codes only a tire pressure error code popped. Temperature looks fine. Do cars have altimeters?

Actually threw a code last night; PO744. We will be looking at the transmission fluid level and if it looks clean. Any other thoughts?