Empty bolt hole on valve cover - please validate

I had my 2018 Taco at the dealer last week to replace three ignition coils that died. I was looking under my hood today and I noticed a clean looking bolt hole in the driver's side valve cover. I am concerned that the technician at the dealership did not bolt something/fasten something back in its's place.

I took a pic below as best as I could. It is a bolt hole located almost directly above the number 4 cylinder ignition coil (drivers side middle ignition coil). It is a deep bolt hole from what I can tell with my inspection camera:



Can someone take a quick look at their 2016+ V6 motor and tell me if they have that bolt hole open, or is something bolted to it? The hole looks pretty clean to me; indicating that a bolt may have been removed and not replaced...

 

https://www.tacomaworld.com/threads/2016-tacoma-spark-plug-replacement.554468/

Relax its fine.

 

You had three coils die at the same time?

 

I can’t tell from your posted pics in the first post of that thread.
I would expect that the open bolt hole that I have in the valve cover would have some sort of contaminate around it or in the inner threads. The inner threads are bright and shiny. I’m still suspecting that something was bolted to it.

 

Ya, I had coils B, D and F fail with corresponding codes P0352, P0354 and P0356. No detectable reason by the dealer for this failure. They replaced the failed coils with new ones under extended warranty.

I had started another thread about it a few days ago.

I need to look at another late model V6 ‘Taco and see. Someone else out there can look at tell me what they see on their drivers side valve cover?

 

There is definitely a plug on the bolt hole missing. I just re-looked at pictures Bishop84 had posted upthread. Why in the Phuck would it have been removed by the service tech at the dealer???

 

He didn’t put the insulation back on by the looks of it. Shit helps keep the engine quieter (minimally though, it really just attracts mice)

 

I need to find a 'Taco locally, going to flag one down and ask the owner if I can check their driver's side valve cover.

 

My 16 with 115k miles. Hole is clean and wide open. I did the plugs awhile back myself and don't remember having extra parts.

No snow,salt or mud yet so she stays pretty clean

 

There a several unused bolt holes on the engine. Normal from factory.

 

Thank you!