Noise when ignition/all power off

[skinny2]

Walked into the garage tonight and heard a noise near the Sienna...sounded like a small pump or fan running. At first I thought one of the fluorescent lights in the ceiling were humming loudly but that wasn't it. Crawled under Ody and the noise was much louder, I would swear it was the fuel pump running. The Sienna had been off for 4-5 hours and sitting untouched in the garage. I opened the hood to see if I could identify the sound from there and within minutes it stopped. This has the smartkey system and the key wasn't anywhere near the van. Does anyone know what this could be or why?

[typesix]

Emissions system is making the noise and it is normal, read about it in owner's manual.

[GTOBill]

Boy, what an absolute NIGHTMARE I had at the dealer, when I had gone in asking about the pump running under my van. At first, they said-"that's not good, we'll check it out...". no one in the (Toyota) dealership knew anything about that pump, nor could they find it. They treated me like I was absolutely insane, and insisted that it must be "tupperware rolling around in the back". In the back of a van, that had been parked for 6 hours! I had to start yelling befor they would take me seriously, and they made some calls, and figured out, that there was indeed a pump there. I DID read the owners manual index, and glossary searching for anything pertaining it, and found nothing. A couple days later, the dealer called me, to let me know, that it was on about page 7 (of 600+), three short lines, stating that "you may hear a pump running 6 hours after shutting off your vehicle, This is normal...."
Now, if I could only figure out how to use the phone in it.... the manual doesn't appear to match the vehicle!

[bullfrog23414]

Can we make this (or at least the concept) a sticky? I realize that we encourage forum members to search, especially newer members, but I agree that it is a hard thing to search for ('noise' probably shows up in 90%+ of our threads).