Cleaned my throttle body yesterday so thought I would post a pic of what it looked like when I pulled it. I have 70K on it. It seems after the cleaning the vibration at idle has been seriously reduced. Took about 30 mins to get all the crud off.

 

It's a dirty job, but well worth it. I noticed a slight increase in mpg's too

 

Nice. Paper gasket? Is the gasket reusable?

 

Mine looked like poop also! After Cleaning, better idle, mileage and overall drivability!

 

As long as you had the camera out, you should have taken an AFTER pic, so we could REALLY appreciate improvement!

 

What did you use to clean that beast ????

 

I highly recommend this piece of maintenance for your hummer. I ran out this morning to clean mine after seeing a couple of tb threads lately and finally a pic. I knew mine was probably equally dirty at 57k and it was. And that pic only shows about 20% of the total grime you need to clean. The inside walls are coated all the way around and you have to open and shut the hatch to get it all...definitely tedious, but you can get the throttle body back to the condition it came from the factory...its clean as a whistle now. I used chain cleaner sparingly to cut thru the dirt with some paper towels. I fired it back up and I can tell a huge difference already at idle, it seemed like a different engine...so crisp and responsive. I cannot wait to drive it to work today, I will let you know the difference in ride and any improvement in mpg(which I think is guaranteed). Thanks for the suggestion and pic. Go clean your throttle bodies fellas!

 

When you have the throttle body off, don't forget to remove the idle air control valve. With the valve removed, it's easy to clean it's plunger and then the associated throttle plate air bypass passage in the throttle body itself.

 

I definitely should have taken the after pic so the difference could be seen. As mthood stated, that really only shows a little of the grime, the sides were mostly dark brown or black.

I used an alcohol-based aerosol solvent. For the throttle body, i think any alcohol-based solvent should be sufficient for cleaning. If the MAF sensor is going to be cleaned while the intake is off it is important to use a solvent that is compatible with the MAF sensor.

The gasket is a resilient rubber compound. It does not come off with the throttle body. I wiped it down before reinstalling the TB, being carefiul not to knock any dirt into the opening.

After driving my normal route yesterday, there is without a doubt an improvement in the idle as well as overall driveability as Tainter said. I will fill-up today and am definitely curious to see if my mileage improves which I believe it should.

 

Cleaned my TB at 61K 5 months ago, and had to clean again this week at 65K..
It was dirty..so quick ?