Wrrrrrrrrrr sound

When I start my 2009 Taco TRD 4x4 and start to drive I often hear a wrrrrring sound that lasts no more than 2 seconds. Sounds like an electric motor and the sound is toward the rear. I’m sure it is normal, been doing that for years since I bought it new, but does anyone know what that sound is? I’m just curious.

 

Like this?

 

Kidding aside. Mine also makes that noise and I've always been curious as to what it is.

 

haters are going to say its a smog pump

 

fuel pump?

 

ABS pump check. Normal

 

LOL'd​

 

Wrrring sound. Not motorboating sound.

 

So what is it...

Smog?
ABS?

 

Im here for the motor boat!

 

Post a sound clip OP

 

Fuel pump. It "Primes" and shuts off (after system is pressurized to 44psi) and turns back on once truck is running, try to get your ear close to the gask tank after you start it and see if the same sound is coming from the tank.

My walbro 255 Pump was loud as hell in my 1st gen.

 

I can’t post a sound clip as it is kind of background noise and would be hard to hear. In addition it only makes the sound when I put it in gear and start to drive. It doesn’t always make the sound. Hard to explain it but it sounds like an electric motor running some kind of hydraulic device. The way it sounds I kind of expect the rear of the truck to raise up an inch or two. It doesn’t of course. Sounds like it comes from the rear of the truck but I’m just not sure. It lasts a max of about 2 seconds or so. It’s obviously not a problem and must be normal but my curiosity has me wondering. I appreciate the responses so far. I figure at least some other gen 2 people hear this on their truck.

 

Abs pump going through it's normal wake-up/pressure check. Mine does it too..

 

That could be the wiper motor - left kiss, right kiss, left kiss, right kiss left kiss, right kiss

 

ABS.

 

@Sig45

Mark....your rig being an '11....you missed the air injection pump and valves by one year.

 

So what's my noise?

 

Your truck = ABS

You = mysterious voices in your head.