EVAP leak and low catalyst efficiency
I have a 2008 GMC Envoy Denali with a 5.3 V8 and I have these three codes and I was wondering if I don't do anything about this will it ruin my engine or make the engine loose power.
The EVAP leak you should fix. It could make your car run like crap.
You can search Scotty's youtube channel he has videos about it. Might be as simple as a gas cap.
The others mean your cats are probably going out. You can read more about that in our FAQ.