Going on a maint binge. (will have a bunch of Q's coming up)
But one thing that has been pestering me for a while is the oil fill cap. It is a bugger to pull out. Turns just fine, just hard to pull out. O-ring just swelled? Tried a bit of grease, but a week later still stuck in there good. Gonna look for a silicone o-ring and try. I'm cheap, but also a tech and not just a parts changer (for the most part) Want to know *why* any part needs to be changed and what caused the failure.

TIA

 

If your cap does not have "SAE 5-W30" printed on it it is not original. If you remove the tube the cap should fit in the hole on the valve cover.

 

Its original. Bought the car new.
Might just pull the tube and polish it's inners.

 

Both my oil fill caps never seized up or tightened up, I apply a few drops of fresh engine oil every oil change.