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TB is throttle body. Between the intake tube and on top of the intake manifold. The IACV is actually connected to it, so if you find one, you found the other.
Spray catalytic converter safe carb/throttle body cleaner into the TB, paying particular attention to the port leading to the IACV, while the engine is running. Either go really slow, or have someone else inside the truck revving it slightly to keep it alive.
#1. Disconnect the intake tube, throttle linkage, IACV and TPS sensor
#2. Unbolt and lift throttle body off of the intake
#3. Unbolt the IACV from the throttle body
#4. Spray the hell out of the throttle body, wiping the carbon off as you go. (There will be alot below the butterfly!) (Be careful and do not spray the TPS)
#5. Spray the IACV port out and use a q tip to scrub the carbon in there.
#6. Once it is completely clean, set it to the side.
#7. Take the IACV and spray the little piston thingy. Scrub it with an old toothbrush or nail brush. Only clean the piston, do not spray into the IACV. In fact, hold it sensor up, piston down, so that it doesn't drip into the sensor.
#8. Replace O ring if damaged or worn.
#9. Once dry, put IACV back into throttle body. (Make sure it goes in straight! I installed my crooked causing a very high idle, so I had to start over)
#10. Tighten bolts, but not to tight. (I made this mistake to and broke one off. Required drilling, retapping, and new bolts.)
#11. Reinstall throttle body back onto manifold. (Check your gasket, or just replace it anyway) Install bolts, sensors, throttle linkage, intake tube.
#12. Turn key to ON for 20 seconds, then off for 10 seconds. (Computer repositions the IACV piston)
#13. Start engine and check for proper idle.
Wmiller, so I should have the truck running while I use the cleaner? I looked up some video's on youtube with people using brushes and clothes to clean the carbon off. Manually moving the piece on the inside..... is this a safe practice on our trucks?