Ticking/knocking sound??

ChevyDude123 · December 19, 2018

So here’s the deal. 1999 Chevy Silverado, 5.3L, 4L60E auto trans, 90k miles on engine (150k on odometer). I have owned the truck a month and driven 2k miles. It seems as though it doesn’t have good power when given throttle, which is something I throw out there for additional info, but what I am asking about is a NEW knocking sound that just started. The video is short as it would only let me upload a very small file size. In my opinion the described sound is most prominent right when the video starts. The sound seems to be originating from the passengers side front of the engine... but I noticed it from inside the cab. If I put my ear on the air intake tube it’s clear as day. It’s not the typical “engine knock or tick” everybody posts about with these engines. I’ve always been able to hear that at start up and it goes away when temperatures come up. I don’t know maintenance on the engine before I had it. The maintenance / little things I have done since owning are replace fuel filter, flush heater core, replace oil & filter with mobil1 5w-30 full synthetic. Oil level is good, coolant level has always remained steady. Fuel pump whines and reduced engine power has me eery it is crapping out slowly, but that is separate in my line of thinking. The knocking sounds like air intake valves or exhaust valves sticking(although idk what that sounds like, but the noise sounds mechanical to me and from that general area) so I am posting this for any ideas you might have?

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