Oil pan cover gone... no idea when and needs some help now

By "all the way back," do you mean back to a horizontal orientation (i.e., almost 180 degrees from its closed position), or only near vertical, just enough to allow draining the oil (about 90 degrees from closed)?

For those of us who can't easily lift the car high for the silly oil-change door to clear the ground, it needs to be detachable, not merely hinged. Someday I'll make that upgrade.

 

By "all the way back", I mean horizontal or 180 degrees. There is a hole you can use to hold it all the way open using one of the clips you remove to open it. Instead, I use a piece of wire coat hanger or a bungee cord to hold it half way open.

 

What Toyota is not good at is spec'ing a plastic thickness and composition appropriate for a flexing hinge. It can be done. The typical tool case, power drill or similar, employs a plastic hinge, and lasts just fine, with many, many openings and closings. Honda uses a similar panel, on the (late) Civic Hybrid, with a large portion hinged. The plastic is much thicker and softer, more like mud flap material. Lasts just fine.

 

The panel is fine, IF you leave that little hinge alone, remove the whole panel at each oil change. That's not as onerous as it sounds, and affords you a better view of the drive shaft boots and so on. And, that's what the Repair Manual says to do.

BUT, the dealership service departments likely won't do that. If you're DIY, the only one involved, and you always take it completely off, you're fine. Otherwise, not so much.

I tried opening the small flap the FIRST time, and when I saw the whole panel reacting, starting to bend, I thought: this is for the birds, no way I'm doing that again.