Hy guys,

every now and then and just for the cruise I'm on, there's this chirping/ticking coming from cylinder #1's part of the valve cover.

Situation:
I go somewhere, hear the chirping someway along the road, go to my destination, leave the car for a random amount of time and when I return and head somewhere else, the chirping does not reappear.
Turning off the engine for just a moment does not help.
Two years ago I heard it for the first time, had my injectors replaced due to other issues and the chirping did not return until this year, so it wasn't the injector.

Sound description:
The frequency increases analog to engine speed.
At idle with the transmission in overdrive it could be about 3 times per second or slightly more.
Chirp, chirp, chirp... or tick, tick, tick...
My ears say it's coming from the cylinder one valve cover area.

I guess it's one of the valves.
Could the valve stem/guide seals be responsible?
Lifters?
Rocker arms?

 

I would be prudent to remove the rocker cover to investigate. If the rocker adjusting nuts are removed while counting the revolutions, it should be relatively safe to reinstall them with the same number of turns and start the engine when the inspection is completed.

Examine the push rods for evidence of rubbing on guides (even though they should be self-aligning rockers), look for scuffing at the push rod socket of the rocker arms, and inspect the spherical pivot and the corresponding space in the rocker arm.

It may be possible to examine the upper portion of the valve stem and guide between the spring wraps, but at least look at the inner (damper) springs for evidence of interference and rubbing.

 

Thanks. Guess there's no way but to look inside.
At least that side doesn't require removal of half the engine to get to it