Car randomly started making this same noise, would get worse if I accelerated, sound comes directly where the timing chain is located. Replaced upper timing chain, sprockets, guides, and tensioner. Replaced lower timing chain tensioner. Still hearing this noise. When troubleshooting, I turned over the engine via crankshaft pulley and seemed the noise was coming from upper chain slapping the top guide. Everything via upper timing has been replaced and both chains are tight. Would it be best to order a lower timing chain kit and replace everything down there as well, or could it be engine internals? Any help would be great.