Engine burning oil and rattling when under a moderate load

What is your question?

We’ve been having issues with our 2014 Kia Rio since it hit 75000 miles. We initially noticed that the engine would start to rattle when it was under a moderate load at low rpms (accelerating from a stop, climbing a hill, etc). We took it in but they could not find anything. Then the engine light came on. When we got it diagnosed they said it was the knock sensor. We got that replaced but the engine light came on again. The system was still reading a knock and the engine rattle was getting worse. They replaced the sensor again, replaced the spark plugs and did a tune up. None of that fixed the engine rattle and after about 5000 miles the light came on again and was reading the same code. We waited on taking it in to the shop because the light would now come on and off periodically. Eventually we started to notice a slight loss of power every time the engine started to rattle and now the engine is burning oil. The oil gets low about every 3 weeks. Any ideas ?

What makes this problem better or worse?

Rattle doesn’t start until the engine is warm and under a moderate load

How long has your 2014 Kia Rio had this problem?

Year