Leaving the 2012 outside and rarely drive it. Went to check oil and saw this ugly *ss crap. Is this a rat's nest? I took a shovel and pushed it off where it lay on top of the engine oil cap. Questions: 1. What damage can it have done, other than rats chewing wires? Car seems to run fine. 2. Can anyone tell how old this nest could be? 3. Will it cause damage that I pushed it off to the side? 4. What should I be asking a mechanic to do that won't cost an arm and a leg? Separate question: 1. How long can oil sit in a car that's rarely driven? It was changed in late December and still enough in there and fairly golden in color. I live in Los Angeles, so hot days are coming. BTW how do I attach an image?
NiMH battery chemistry is ideal for constant use and expensive/problematic with rare to irregular use. Why are you holding on to a car you don't really need? How much would you sell it for?
Have him look over the engine bay, looking for chewed wiring, whatever. Good to check the cabin filter area too (requires glove box removal). Wouldn’t hurt to check engine air filter and associated plastic as well, they might set up residence in there as well. If there’s evidence in the cabin filter area it’d be best to remove wipers, associated linkage/motor, and the underlying metal cowl, this’ll expose the cabin filter egress: check the area and mesh the opening with 1/4” spacing, galvanized steel mesh, secured with sheet metal screws. What are you using to post, phone or computer? the hands-down simplest is to copy the image, then paste. For example on my iphone, took a screenshot, cropped it, chose copy, then tapped in the following space, and pasted: If you’ve got a saved image, you can tap/click this button: then navigate to and select an image, which attaches the image. You can leave it thus, it’ll appear as a link at bottom of your post, or embed in the post, either full or thumbnail:
Get a cabin air filter with a wire screen. The reusable K&N model us a good option. Put a stainless steel screen on the air intake.
IMHO; that needs to be cleaned out and the engine compartment and cabin filter inspected. You should probably sell it, if your not following OEM storage procedures for that car. Your basically slowly killing the traction battery pack by idling the car like that. Hybrids require some specialized care; unlike ICE only cars. https://assets.sia.toyota.com/publications/en/om-s/OM47704U/pdf/OM47704U.pdf
I think it looks like a rats nest, hood insulation part of the material. As others have said (myself included), that's likely just the tip of the iceberg; you need to do stuff.
