Broken cabin air intake baffles?

I took the cowl apart to replace struts and spark plugs on our 2013 Prius V, and the two plastic baffles that isolate the intake for the cabin HVAC systems are both broken. I'm baffled at how this could have happened. At 132k miles, the plugs all had blowby discoloration on the insulators, and one strut was completely blown, so I'm pretty sure that the cowl hasn't been off before.

New parts were cheap enough at a little more than $20 each, and replacing them looks like just extracting them and snapping new ones into the clips after removing just the black plastic cowl cover, but what could have broken both of them? I also discovered that the cabin air filter was missing (we just bought it a few weeks ago), so I'll probably have to clean out the plenum. Lots of leaves and gunk all over the sheet metal cowl pan under the plastic one, and that must have gotten in there through the broken baffles.

I went with the Denso OEM plugs and KYB struts and shocks. It drives like new now.

 

They'd have to be pretty beefy rodents to snap both pieces the way these are broken, but there wasn't a clean break with mating jigsaw shapes. My first instinct was to try Krazy Glue, but that requires a close fit.

They're sandwiched between the sheetmetal pan and the plastic cowl cover, with foam weatherstrip that was obviously old but still intact. They have little springy plastic clips on the bottom that snap into holes into little raised mounts on the pan, and the plastic cowl cover would compress the weatherstripping to seal the air duct. The only opening to the environment is the plastic grille and its backing screen, both of which were perfect aside from a few stray pine needles.

No other evidence that would suggest rodents. These are broken into pieces. There are slots in each one. The larger outboard baffle has a low slot for the thick windshield wiper wiring harness, and the inboard baffle has a larger horizontal slot that appears to accommodate the movement of the wiper mechanism. I suppose the mechanism could have gotten out of alignment and fouled on the inboard baffle, but it was solidly secured in it's four attachment bolts.

One tip if you're going to remove the cowl for these or other tasks: the plastic cowl cover has two little extensions on either end. These just lift out vertically from little integrated clips. The cover is then shortened enough for easy removal. Don't ask how I figured it out...

 

Definitely broken, as in chunks.

 

Awww, they're so cute! Enjoying the view from the comfy nest the human provided. I haven't dug far enough into it yet to see what may have gotten into that plenum in the absence of the cabin air filter. We bought the vehicle a couple of months ago, and it needed immediate attention to the rear wheel bearings and suspension. One strut completely blown, but the other one and the shocks were just getting tired. At 130k miles, I figured spark plugs too while the cowl was off, and they all had serious blowby stains.

How durable are the Prius coils? We had several fail on a high-mileage (180k miles) Matrix, but those were right up front, so simple to replace. Ditto the injectors.

But I digress. No red squirrels around here, just lots of grey squirrels in the trees. It was an SF Bay Area car, so I don't know about previous rodent environments. Is it straightforward to get into the plenum and clean it out? How do they get in there? Up the ducts from inside, or somehow under the hood from below? The plastic grille and screens on our cowl are intact, so they couldn't use the air entrance, right?

The windshield does seem very nice for the age and miles, so I guess careless techs could mash the baffles if they jammed the cowl back on. And I suppose that the absence of clean, glueable breaks would suggest critters nibbling.

Anyway, new parts are on the way. Thanks for the input!

 

Okay, I just went out and dug a little deeper. Took the glovebox door off, started the car, and switched back and forth on the recirculation setting, so I could see how it works. I thought those squirrels had eaten the whole opening of what I realize now is the return port for recirculation. Ours has also been chewed on, but the original contours of the right side look untouched. Definitely a whiff of rodent restroom on close inspection.

And, looking at the broken baffle piece I kept out when I put the cowl back on, definitely bite marks, which would explain no clean lines to try gluing back together.

I guess those squirrels just wanted a little more legroom in their corrugated nest?

How much work to extract the box for a thorough cleaning? Ironic that the squirrel-cage blower is right below the filter, eh? Our AC odor did smell more like urine than mold, so I guess we've tracked it down. How extensive is the stink likely to be further down in the ducts, and what's the best way to clean them?

 

Ok, now it's getting weird. After studying the crude parts drawings in an online Toyota parts catalog, I ordered what I thought were the right baffles. What arrived were what ChapmanF describes above, hinged pieces that don't look like ours. I called the dealer (about 90 miles away--our local outlet jacks parts prices above list), and the online guy spent 15 minutes digging in catalogs. He emailed the images from the catalog, and they were in the right place along the cowl. He started to read the part numbers for a new order, and they were the same as on our invoice.

Apparently there's a glitch in the catalog. When I can block out some time, I have to take the cowl apart again and take photos of what's in our Prius so he can try to track the correct parts down.

He said that things like that happen all the time. Sigh.