2006 Prerunner oil fill cap question

Was checking the oil and oil fill cap on the 2006 Prerunner 4.0L I purchased a couple of weeks ago, and noticed a small bit of that light tan colored goo on the oil filler cap. The oil on the dipstick looked perfectly clean, and with the engine running I could see the oil down in the engine through the filler tube squirting and moving around, perfectly clean and clear...

Is this a big concern? Is the tan colored stuff on the inside of the oil filler cap possibly due to the dealer power washing the engine bay and maybe some water got into that cap and mixed with the oil, or possibly some condensation on the inside of the cap (we recently had some major rain/snow)? I know the engine bay got power washed recently, there's pretty good evidence of water splashing all around.

I cleaned up the cap and am going to keep an eye on the oil pretty closely for the next few days and see if any of that oil/water mixture seems to reappear. BTW, the engine has 49.6k, and there is no evidence anywhere else of water/oil leaks. Should I look for anything else in particular? Thanks. I'm still a 2nd gen newbie

 

Great. I was hoping that might be the case.

 

Chris is right (like usual), with short trips, the engine hasn't had sufficient time to warm up and thus the moisture hasn't had time to evaporate. If you take shorter trips, I would suggest changing your oil more frequently than if you mostly traveled on highways.

 

I checked out a 2010 v6 spd tacoma last weekend, and noticed the same...slight tan build-up under cap.

I guess it's the heavier tan sludge you should worry about.

 

Changed the oil in my 09 and I noticed a nickel sized amount.

No biggee, wiped it off and called it good.