2016 Elantra GT automatic
 

Hello friends!
Today I had to drive over a larger hill. Have never had any issues with vehicle since buying it new.Now has 101,000 miles. I noticed that it was having trouble climbing the hill at posted speed limit, applied more gas and it started to bog down and the check engine light came on for just a couple of seconds and went back off. Did not sound like a transmission issue, no smells and vehicle has been serviced as required. On level ground seems fine, but adding acceleration to climb a hill it bogs down. Check for codes and nothing even though the engine light did come on for a few seconds. What next?

Not knowing how you checked for codes, the next time this happens , check for codes before shutting off the vehicle.
Some codes will erase when the power is removed from the system and modules are allowed to reset.

What does "Service as required" mean? If it was only oil changes, that could be part of the problem.
When was the fuel filter replaced?

It has been serviced only at the dealership at the required intervals. We received a recall notice and dropped it off at the dealer yesterday. Hope to have more information this week. I will post the findings as soon as we are advised. Also having the 100,000 mile service done as it just hit that milestone.Fuel filter did cross my mind especially since there were no codes and this is the first issue we have ever had. It even still has life left in the original brake pads! Third set of tires though!

A fuel filter problem will not show any codes stating fuel filter problem.
Fuel contamination or restricted filter will produce performance problems and possibly some code(s) that one of those items can affect.