Fluffy grey insulation (?) with tiny red strings coming out of drivers left vent on '87 4WD Turbo RX. About the size of a golf ball, every once in a while. I don't run the ac. Don't see insulation in any other vents.

 

A few pin oak leaves in there too but more concerned about where the insulation is coming FROM. Any ideas?

sounds like rodent nest to me.

Yeah....there is no 'insulation' down in the HVAC system. Other than the fur wrapped around whatever mouse is lounging in there.

Mice think Subarus are great, too!  Any Subaru here that sits for 2+ days risks mice moving into the vent system.

Round here they stash plum seeds and acorns ontop of the block, under the intake........I swear they are roasting them.

Round here they stash plum seeds and acorns ontop of the block, under the intake........I swear they are roasting them.

 

The wifes 05 Outback had a big stash on the top of the block, took a pressure washer to get it all out.

The spare tire in the engine bay makes a perfect drying rack for acorns, if what I found after it sitting over the winter is any indication. 

Pesky varmints really love the sound deadening material under the carpet. Sounds like what you found from the description.

 

If you remove the plastic grilles for the cowl area, you'll most likely find the nest in the opening for the heater air intake.

Same for the opening for the fresh air intake on the driver's side.

haha found acorns in mine when i got it also smells like a rat died in the air vents 

I had them three months after purchasing the car new in 1994. Dealer got two garbage bags full of stuff out of the vents.  I ended up buying screening material and put it over the vent inlet of the cowl. Caught many a meece with snap traps under the hood too.

 

The place I live now has lots of cats on patrol. Shreds the meeces to pieces.

 

Edited June 30, 201312 yr by MR_Loyale

Yep, sounds like a pack rat. I remember a car my dad had that a pack rat had gotten into and had stuffed the whole heater box full of dog food. Unfortunately we didn't find out about it till we turned the heater on and the smell was awful