Printer will not hold temperature any tips or suggestions?

so i have tried various and numerous different .stl files off thingy verse mainly calibration cubes and for some odd reason all the sudden every single print it does the same thing and prints a little thin wall. and thats it . anyone ever had this issue ? ill post a video on youtube and then upload it here …

please see videos what would randomly cause this?.. i have no idea whats going on its worked fine for almost 3 yrs till my laptop crashed and i got a new laptop windows 10 now this .
NOTE: i currently have .Jpods marlin software run through an Raspberry Pi 3 setup ran on Octoprint slicing with slic3r. - i followed
Joe Doubek’s youtube video on setting up and modding the Z pro…


well i figured it out … SMH!. for those who have a tap holder printed and side mount it like i do be careful where you put it… i noticed finally that RED tape holder in my video. i placed by accident infront of the Z-stop deal… and it had slid and hit the Z-stop … sooooo moved it back and shes operational once again!.BUT now i am having a issue where the Zee Pro where it does not seem to want to hold the 180 C i run it at 190 better yet… it keeps dropping to 167 once the fans kick on ? i dont get it though bc like i said before i ran printed many of item over the last couple yrs and it just started acting up .

In my case, the channel of the fan had several unwanted openings due to the heat radiation of the heaterblocks. First I closed the gaps with 2-component glue and limited the Fan-power to 35%. Worked fine then.

well i think i found my issue i was running the printer for a while . i initially encountered the clicking nose in the head printer, so i pulled it all apart found removed the jammed up filament and cleaned the feed motors gear deal off. then left the head cover off and all that for a while until i read on here some where some guy said the plastic cover and the rubber grommet are a must use . when using the stock print head as is . now i am getting a little bit of Z banding when i try the 40mm test cubes its like it prints nice but you can see the Z fading into the print ill post a picture . i did 3 prints at different speeds with differnt cooling settings and all that all did the exact same thing . think i may need to lub some things up or adjust something . any tips?