Rectangular Box Under Spare Tire Housing

[BillThompsonMirage-ES-CVT]

I own a 2014 ES with CVT. I was looking at the rear underside of the car at the rear end. I noticed a rectangular box about 10 inches by 12 inches in size with a depth about 1.5 inches located directly under the spare tire housing. Any one know what it is?

[Canoehead]

I also noticed that. I asked the sales guy. He didn't know either. I think I speculated it might be some sort of fuel pump and he agreed (but neither of us have a clue!)

[3dplane]

It is the evaporative emissions charcoal canister. It stores fuel vapors and the engine uses it under the right circumstances.

[Canoehead]

It is the evaporative emissions charcoal canister. It stores fuel vapors and the engine uses it under the right circumstances.

So for a little extra speed you just have the fireman shovel on a bit more coal? I like the sound of that - a hybrid powered by both a gasoline engine and a steam plant! Choo Choo!

Your explanation makes way more sense than my guess, though. Thanks!

[BillThompsonMirage-ES-CVT]

Thank you, 3dplane. I wonder if any maintenance is required on it.

[Cani Lupine]

I thought it was data logging equipment, like the "black box" you'd find on a plane.

[IchabodCrane]

So why isn't it in the engine bay like almost every other car on this planet?
Could it be relocated?

[Canoehead]

So why isn't it in the engine bay like almost every other car on this planet?
Could it be relocated?

I would further speculate that, especially with the lack of a rear anti-sway bar, that bit of vapor provides the necessary ballast to keep the wee car upright though turns!

[3dplane]

No maintenance required or possible on the canister.

The black box guess is pretty funny!

They typically fail by coming apart on the inside and get clogged,sometimes contaminating or ruining the vent valve and/or purge valve depending on the system,setting an EVAP related DTC.(Diagnostic Trouble Code). Hopefully many many years from now.

It could be located anywhere,it is a matter of routing thick and thin vapor/vacuum lines between tank,canister,purge valve,vent valve plus electrical wiring etc.

Most trucks and SUVs have it near the tank and I can not remember seeing one under the hood of newer cars. I guess older cars had them under the hood.

[rednwhitecooper]

It is located under the hood in some markets. It mounts to the pedestal that protrudes from the firewall behind the engine.