Hello I have a 2014 Gmc Terrain AWD Automatic with 94758 miles. About 3000 miles ago I had the common problem with the eco tech 2.4L engine and my timing chain blew. I got it fixed but now it's running loud I figured it may be because of the carbon build up from the valves leaking oil into the engine. My question is could it help if I use some stp synthetic engine flush to try and get the gunk out? Could that help it run quiter?
Was the engine rebuilt along with replacing the timing chain? The GM Ecotec 2.4 is an interference engine. When your timing chain broke, the pistons crashed into the valves. This will bend valves and can even crack or punch holes in pistons. When pistons contact the valves something has to give. If the timing chain was replaced and nothing else was done it's a surprise that it's running at all.
https://tuningpro.co/the-4-most-common-gm-2-4l-ecotec-engine-problems/
The engine was not rebuilt and runs perfectly fine currently its just lound.