Help! This one's for car talk Strange sound from behind glovebox/passenger wheel well

This is really strange....its a lengthy explanation, but maybe you can help
OK, I started the tuck up this morning to go to work, really cold and snowing a little today, I think it was around 2* at my house. Let it warm up for probably 5 mins and pulled out of the driveway

As I head down my road, I hear what sounds like a small rodent trapped somewhere behind my glovebox, or in the passenger side dash, scurrying around in there and trying to escape. A little dull bumping sound accompanies by a higher pitched screeching, scurrying noise...a familiar sound to me, lol
I've had mountain packrats build nests in AC vents and engine block of past vehicles a few times before, so I immediately think there must be something up in my engine bay trying to get out, would make sense given how cold its been the last few days. I pull over, pop the hood....nothing, engine bay is completely clean. I looked under the passenger side wheel well, at cv boots and all linkages, everything looks fine.
What's more, the noise stops when I stop the truck. I reved the engine while still stopped, no noise.
I start moving again, the noise starts up again, I turn off the blower fan, the noise continues. When I accelerate, the noise DOES NOT change in frequency or pitch. It's totally irregular (like a small cat trapped in a slate-lined shoe box trying to get out)
I had to get to work, so I put up with it in the way to the ski basin. It was around 0* this morning in the parking lot. I figured, if it is a little animal stuck up in there, he's gonna get out over the course of the day or freeze to death.
I get back to the truck this afternoon, still snowing and cold as hell, pull out of the lot and the noise it still there...allll the way home. I thought maybe its a 4-wheel drive linkage, switched to 2-wheel drive, still there. Driving up my road, I thought I could here a heavy thud coming from the right front wheel well in addition to the noise, but need to confirm this
Checked my cabin filter for crap or any clues and found nothing but a few leaves
The truck is driving just fine in handling and all

So....any ideas???

 

wanting to go out tonight, but not sure if I should be driving....bump

 

gnomes?

 

I think its the extremely cold weather causing your problem.

 

Seems like quite a few people are having problems w/rodents lately. I forget who posted it,but he had one or both of his coolant hoses chewed through.

 

http://www.tacomaworld.com/forum/2n...n-mouse-mice-rodent-inside-my-air-system.html

 

As I said, I pulled the cabin filter and the fan, no signs of 'em

And, the noise continues of the fan is completely OFF

 

I'm having a hard time thinking its a rodent, as I said, I checked the cabin filter and blower fan (I have the dreaded fan chirp noise, and this isn different), plus I don't smell anything, the heat from the a/c smells just fine, which would not be the case if there was a nest anywhere. Also, when I go below about 5mph, the noise stops, speeding up brings it right back, I can make the noise on command, if you will

 

I hope your right, but I can imagine what that is

 

Check the air intake where it meets the right fender. I was getting vibration noises that started when it got cold. You have to remove the washer reservoir to get to the bottom. If you push the gasket in it might stop the noise.

 

Once had co-workers put one of these under my rear seat as a practical joke.

 

I had a strange noise at around 2000 rpm only in cold weather behind the glove box. Even when the fan was off. Sounded like what you are describing I think. It was the group of wires that enter the cabin through the firewall. Pop the hood and locate the bunch of wires that enter approximately in front of the glove box. There's a metal bracket that supports the wires before they enter the cabin. I pushed down hard on the bracket and bent it some to give the wires more tension. It's been 2 years and no more strange annoying buzzing/vibrating sounds. Not sure if that's your problem or not though but if so it's worth a try.

 

Interesting, I'll check this out, I dont remember a group of wires like that on the passenger side. The noise doesn't seems to be related to a bumpy road surface at all either, but I'll look, thanks

 

Didn't happen with bumps, just at a certain rpm. And never in neutral, only when in gear. At a stop with truck in drive and foot on brake it'd do it. Shift to neutral and it'd stop. Made diagnosing it difficult!

 

OK, it does it at 5mph or 50 mph, same noise, only sometimes louder at speed. In neutral or in gear, same noise.
Does not seem suspension related, as it'll do it on a smooth section of road and my bumpy dirt road. I checked that metal holding bracket you spoke of, its firmly holding those wires in place

This is maddening

 

one of our Tacoma at work has some noise coming from the front right side. Turned out it was a lose mud flap, causing the fender liner to rattle causing a rumbling sound.

Mine has a light plastic rumbling sound too. I'm bringing it to the dealer this week to let them deal with it cause it's so new.

 

my front flaps are removed, and the fact that the noise continues, even at 5mph, makes me think it isn't my fender

 

I have a sound coming from the passenger side, but it sounds more like a compressor type sound cycling on and off. Sometimes it will kick in two or three times within a mile. The dealership hears the sound, has eliminated the air pump. It is more evident when driving in city, at about 25 mph. My truck only has 7K miles and started at about 3K.

 

possibly a dried dead leaf or piece of paper stuck in the air intake for the heater/AC vibrating with air flow or harmonically with vehicle vibrations