For additional information about Cleaning the
Have you ever noticed a loud hum and/or whine (whining) coming from your
engine bay? Or more specifically your intake area? Well, more often than not,
this is due to a dirty IAC (Idle Air Control) Valve. Since everyone is always
asking about it, hopefully this will help.
Two 10mm bolts to remove, and unclip the electricals:
Here's the dirty intake's connection with the IAC:
Turn the valve to notice two chambers. Inside one of them you will see a spring. Inside the other, you will probably see a bunch of dirt coating what should be an exposed sensor. Spray the Electrical parts cleaner liberally, directly into the opening, and watch until the liquid coming out of the valve is clear (white). Set the IAC on a towel or clean surface and allow any other liquid to drain and the sensor to fully dry. Here's a picture of a clean IAC valve (underside):
And don't forget to clean the sensor below the black snap off cap on the side of the IAC valve:
After allowing to dry, replace the IAC and start your truck. You should allow the engine to warm up for a few minutes and the computer will re-learn how much air to allow into the engine at idle.
I experienced a much LOUDER whine after doing this for the remainder of the day, but I only allowed the liquid to drain for about 2 minutes. The whine hasn't returned in two days since, so I'm guessing the liquid cleaner wasn't completely drained when I replaced the IAC Valve. Just a warning in case you are anxious like me.