Whirring noise for a minute or so at cold start NOT affected by RPM

This makes so much sense I feel stupid for not remembering that assembly under the hood. In my defense, (excuse,) I was out of town for a month and then there was a ton of rain to deal with.
I am all but certain this is the culprit. Thank you for the pdf. That will help me a great deal.

 

I was also going to mention removing the belts and running the truck for a short minute but after listening to the video , it sounds like the classic air pump sound .
The AC compressor in these trucks also runs when cold to remove any moisture inside the cab . I hate the feature because you wear out your ac compressor anytime you use defrost in the cooler months . There is a mod that can be performed to keep the ac off while in defrost .
That air pump looks easy to diagnose . POP the wires off and block the tube during a cold start up

 

Thank you. Great idea.

 

Based on the initial complaint and price of overall repairs I'm going to say you have an AIR injection valve that is stuck and the air pump is working double duty which is causing the CEL to pop up. That system is disgustingly overpriced by Toyota, so the more I think about it, the more it has to be your AIR injection system based on the noise complaint, time of operation, and the price of overall repairs.

 

Thank you. I really appreciate the help from everyone here.

 

See... wait until morning.

 

Finally had time to replace the secondary air pump on my 2008 Tacoma Access Cab base. 2.7

I found a part on Amazon for $140 and it has good reviews. The whole project took about 30 minutes top to bottom because I was experimenting and partially disassembling the old one. The new part fits and works perfectly. The only odd thing I found is that the old one had about 3-4 ounces of water in the rubber bottom part. The bottom of the motor was a bit corroded by this water. It just smelled of rubber and not mold so the dry desert air won out on that count.

Bottom line, do NOT let anyone do any detailing where they spray water in the engine compartment area while the engine is running. The intake apparently can suck water in and it doesn't go away. I know this happened last fall when I had some work done and my guy is super vigilant in cleaning things up, but I do remember him spraying water while the engine was running. If you do this, tape some plastic wrap over the intake or something. This part lasted for 10 years and was still working if a little noisy at start-up but I believe water accelerated the aging and noisiness.

HUGE THANK YOU to all here on this site. I have now fixed two things on my truck that could have been much more expensive otherwise.

 

There is no foam inside this assembly from my experience. It was a bearing that was starting to fail I think from water accelerating the corrosion.