tick at idle but not all the time. I pulled valve covers. all the rockers are tight. Where to go from here?IMG_1852.MOVDownload MOV
The light tick like that is typically from a pitted or damaged roller on the lifter. When this happens it wipes out the cam lobe. To check it use a stethoscope or screwdriver on the rocker bolts to identify what one makes the noise. Then use a dial indicator just like I do in this video https://youtu.be/0YPPsYbffAA and at 9:50 is when I used a dial indicator. It's fairly common on the newer direct injection engines because the camshaft is such a soft metal. Hopefully I'm rong for your sake. If I'm not though, you may as well do a full delete at that point.
running AND cranking compression test. compare results. my 2014 v6 ecotec had HIGH compression on an AFM cyl while running. but cranking they were equal. found a wiped cam lobe... not opening the valve enough/long enough. It sucked and I hope its not your case. I didnt have a tick though, my lifter was not collapsed.