NHTSA Complaint #11719683 — 2021 KIA SELTOS

My engine was replaced April 9. 2025 because of piston issues. I had taken it in a few weeks prior for terrible grinding noise, shaking, and slowing down. They didn't find anything wrong. It happened for a short time twice after and didn't take in as sporadic and would stop. Then it happened again for longer time. I had it towed to Kia again. During time in shop, I received a recall letter. Shop kept saying it would be done next day. After a few days I called and they said they were putting in an engine. I Picked it up and then two weeks before Christmas It started grinding sound and shaking etc. It was towed into Kia I bought from as my Kia roadside had expired a few days before. They ran diagnostic test and said they found nothing. I told they to try harder. Ran another test and supposedly according to some bulletin they upgraded some software back to what it was before engine replaced and the problem should be fixed. Only drove car 1 mile according to service papers I have. I have a 5 year old car with 24,000-25,000 mi. on and I am afraid to drive it. So far it has only happened when driving 45 mph or less. I will not drive it on turnpike or interstate. I want this recorded someplace so it is on the record for other with this issue.