Under valve cover of a 2AZ-FE

[LeakySeals]

You asked if there should be concern. For this engine yes. Molakule is right, but its also true that heat/flashing/volatility can cause varnish. The latter is the case on this engine. I fixed one, assisted with a few others. Its always the same 3 bolts. At the intake manifold. Where the aluminum block is at its thinnest. (piston on one side, coolant channel on the other). What makes aluminum threads strip? Heat. It gets soft. Under torque the bolts can pop loose. Will it happen? Maybe, maybe not. If you look at the block design, clearly the coolant is playing a role keeping that section of the engine cool. So I suggested keeping on top of your coolant, because I think thats what causes/exposes the problem.

Concern means keep an eye on engine temps, does not mean the sky is about to fall. was just answering your question. Nothing unusual about the pics for your engine. Here's another one, same thing. Hot oil vapors rising on the cover just like yours.

 

[KitaCam]

Here's the top end, what was under the valve cover leaky posted above...note no more varnishing/wear on the same 2 lobes as on other cams or yours...so do keep an eye on them...

and a close-up

I'd check the pcv valve...it clogged it could add to the vapor blow-by...and residue build-up

 

[KitaCam]

Someone said something about what you can see behind the oil filler hole...where's what you can see...

btw...when these pix were taken, this 2AZ-FE had Shell 5w-30 conventional OCIs to 97.5k miles and 3k with PYP since...after the pix it got PP 5w-30 and will have syn in it for 5-6k mi OCIs

This is the area under the filler hole baffle and note that the darker areas are lighter than the above pic, which I attribute to 3k miles with PYB since the above pic was taken...maybe...

...aaaahhhhnnnnd, when the coolant was drained @ 100k it wahhhsss ugly...likely the first in a lonnnnnnnng time for this 05 Camry...

 

[javacontour]

I did the VC gasket of oilBabe's '02 Camry, now being driven by SD. It has 247K miles and the VC looked just a bit dirtier than those pics.

The engine looked the same.

It was leaking on the front curbside of the engine, onto the serpentine belt, so I changed the gasket and the belt.

She checks the oil at every fuel stop as she knows if this car runs out of oil she's walking. It still burns it, as I see that puff of blue smoke when it starts. But after 247K, I expect some burning.

I suspect there at leaks at the bottom end too, but at this mileage, I'm not going to address those. Oil is pretty cheap compared to the labor needed to address seals and gaskets down there.