Starting having the typical chain rattling about 2 weeks ago, then about a day after that started I believe timing became off because started to have really jerky/stuttering acceleration. Been driving still because this is my only way to and from work. Mechanic looked at it recommended an engine replacement which will cost me around 3600$ for a used engine with 183000kms (mine only has 143000) timing chain full replacement will cost me around 2500$. Mechanic said it could’ve bent valves or caused other internal damage but I was under the understanding that the gm ly7 is a non interference engine. I’m just not sure what to do because I’m a teenager and cannot afford to start getting into valve replacements and heavy bottom end work but saving the 1000$ would help me out a ton and I’d get to keep the car with an engine that i know more if it’s history rather than a random junkyard engine that could’ve been maintained like shit.