Heater Help

Hey folks.

Have a 2017 Tacoma, SR Extended cab, basic AC system.

Had to use the heat for the first time since Spring this week, and it smells like something crawled up in there and died. It's not mold. I know mold. This is dead, rotting animal. The smell is ONLY when the heat is on, any vent position. When I have it on the cold side, no odor. As soon as I turn to the heat, even a little, the smell starts rolling in strong.

Where should I start looking, how much of my cab am I disassembling.

Thanks.

 

I'd first check the cabin filter behind the glove box. Hopefully you'll find the issue there. Getting to the heater core in the middle of the dash is not an easy job and would only do that as a last resort.

 

Also take a peek by the window cowling which is where the hvac intake is. Also try it on recirc mode aswell

 

I haven't checked those, but I've ruled them out since the smell is only with heat. With AC, there is no smell, with or without recirc

 

As vaca mentioned, getting to the heater core is no easy task, on any vehicle really. You're basically having to take out the entire dash

Are there any other signs of animal intrusion? I was going to recommend just leaving the heat on and windows open for a hour or 2 to see if that helps. But if there's truly something dead in there, maybe that'd make it worse?

 

Pooph or Febreeze might help out some.

 

I was afraid of that. I miss my obs f150 and it's heater core that could be pulled through the glove box.
Anyone that's had to pull it know how long it'll take, or how much to expect a dealership to hit me for?

 

I believe the air flows through the heater core all the time even when using AC.

Before you start dissembling anything try putting the heat on full with the fan on mid speed and take a drive with the windows down, see if it goes away.

It doesn't have a vaguely sweet smell by chance? Sometimes the heater core will leak, hope it isn't that.

 

To clarify. It is dead animal smell. I'm familiar with mold, coolant leak, and rotting corpse smell. 100% a rotting corpse smell .

 

I checked the cabin air filter, big signs of rodent activity, very frustrating. What's this other pie e y'all wanted me to check? The black hood trim?

 

Recirc is on with ac so try just outside air only(no heat, defrost or ac). If you get the dead animal smell it might be under the engine cowl and not inside the vents. Critters often nest in that space which isn’t screened from the wheel wells.

 

Okay, I dug in. Pulled the windshield cowl, found a hole chewed in the cabin air intake and the cabin air filter full of droppings and fur. Also found where the bastard got out by chewing through my air filter lid.
Gonna replace the air filter, it didn't smell bad, but its in horrid condition. Put some wire mesh over the air intake to prevent this from happening again and go from there.
With truck off, I ran the fan and moved the temperature selector, and got no odor, so I'm optimistic.
I did notice a little odor with recirc ON. But we'll see after these replacements and go from there.

 

Darn varmints! They certainly can wreak havoc on a vehicle!

 

As frustrating as this is at least they didn't chew the wiring harness up.

We have had folks in that situation where the repair was thousands of dollars.

Hope this is the end of your problems.