Dealers charge way too much for parts, you can get the throttle body gaskets from rockauto, or amazon, for a few bucks, also your local parts stores sell them.

Do I have to disconnect battery before removing IAC to clean? The reason I ask is because I found out that my 2001 Buick Century does not have a radio code that I can reset on my own. I would have to get dealer to reset and they charge $85 for this.

no, but if the radio is the newer style you dont need to reset it. i know it varies with the different cars but i thought they stopped using that style about 2000. and if you do you can turn the security off if you get in the manual. its off on my 98

As Justin said, no need to disconnect the battery, if you ever have to disconnect it, and you are prompted with LOC on the radio, then you should be able to unlock it yourself, I'll paste the how-to info copied from another site.
----------------------------
1. Press and hold presets 2 and 3 for about 5 to 10 seconds until you
get 3 digits on your display. This is the first 3 of 6 digits you will
need, so write 'em down.

2. After doing step one and writing down the code, immediately press
the
AM/FM button to get the last 3 of the 6 numbers you'll need, and write
'em down. (if you wait too long between steps 1 and 2 and the LOC code
displays again, just start over).

3. Call this number, it'* a prerecorded message, so don't worry about
having to talk to anyone...1-800-537-5140. The voice will ask if
you're
calling for Chevy, Pontiac, Cadillac, etc... When you hear him tell
you
to press "2" for Pontiac, press 202107 and hit the # key. He'll ask
you
for the 6 digit code that you've written down. Enter that and press
the
* key. He will then give you a code, and the option to get additional
4
digit code, but one should be sufficient.

4. Follow the normal procedure in your owners manual for unlocking the
radio with your new code...press the hour set button on your radio
until
you get the first two numbers of the code, then press the minute set
button until you've entered the last two numbers. Immediately press
the
AM/FM button once the correct code is entered and the code SEC or
"secured" will be displayed on the display screen. Now, just turn the
radio on, and your ready to roll.

There is an additional step you can take to remove all codes from the
radio and start from scratch by entering your own personalized 4 digit
code so that it won't get you in a pickle again! Just repeat step 4
and
you should get a display screen that reads ---. This means the code is
out, and you can now program your own code. Of course, once you
receive
the 4 digit code from the GM recorded message, just keep it in a safe
place, because you can use that same code again and again should you
have any more problems with it in the future..

Thanks William and Justin! This forum is a such a great help!

I got this car used so don't know if previous owner enabled radio Theftlock security. According to owners manual if Theftlock was enabled there should be a light that is lit. Unfortunately the radio has a few blown backlight bulbs so I'm wasn't sure if the Theftlock bulb was working or not. But now with William'* useful post I don't have to worry about resetting radio. This is great!!!