Hey everyone, I just bought a 1992 Jeep Cherokee Laredo with 155,000 miles on it. It is pretty much entirely stock and is in great condition aesthetically. Despite the low miles on the engine I have noticed a clicking sound coming from the engine that doesn't go away at different RPM's or while in gear. Earlier today I removed the valve cover to see if I could pinpoint the location of the clinking sound (On a side note, it all seemed really clean. No grime or foam or discoloration as far as I could tell). While it was removed I reattached the throttle body and started it up. The clicking sound seems to be coming from one of those little springs below one of the rocker arms. I think it might be deeper within the cylinder head but I am not sure. Is this a common thing that anyone else has come across and might be able to diagnose without me having to remove it from the engine block? Please excuse my lack of technical jargon, still pretty new to this. I'd appreciate all and any criticism. Thanks!
-Attached is a picture and a video of the engine running with the valve cover removed

 

Sounds pretty similar to my 96.
Injectors or the thing circled in this picture that I can't remember the name of is what comes to mind.

 

Noise sounds like a pretty typical 4.0.

Spencer_P that would be the evap canister purge solenoid. When mine went it had a bit more of a "chug" sound to it than OP's noise.

 

Change the oil and use a quality filter. Wix or Mopar will be fine.

I prefer Rotella T4 oil in 15w40 for the 4.0s.