Try cleaning your throttle body and using a can of SeaFoam cleaner.
You can buy both at Auto Zone for a combined cost of less then $12.00.
It takes about ten minutes to clean the throttle body and you just
pour the SeaFoam in the gas tank.  I can't help you with the IAT
sensor.

the injector should be replaced and be sure to change the hoses and o
rings when you do the injector.  Also, the inlet air temperature sensor
is in the intake duct that goes to the engine.  It is between the filter
housing and the intake.  The noise you are experiencing or flutter as
you call it could be the variable valve timing.  You never said if the
car ran properly?  If the car runs good other than the idle problem be
sure to check the intake hose between the intake and the filter housing
as an air leak would cause the flutter and noise.  The last one I worked
on was cracked from the under hood heat and it was a small crack in the
accordian seam.  It opened up sometimes and that caused the flutter.  A
new intake hose fixed the problem.

How do you know it's a clogged injector?  Are you getting any Check Engine
lights?  A failed injector will generally give you a "Injector Circuitry" or
"Injector Leak" ECU code.

First thing I'd do is run some injector cleaner through the system (Techron
cleaner is good).  Then clean the throttle body.  Both are easy and cheap.
I'd remove the throttle body to clean it rather than trying to clean it on
the car.  You'll need to buy a new gasket for it, but that's really cheap (<
$10).

Second, replacing the injector should be a last resort.  If you do replace
just one, it must match the others.  There are two "styles" of injectors,
one has a blue dot, and one has a red dot.  They are essentially the same,
but they MUST all match.  Otherwise, the ECU won't be able to adjust the
fuel flow rate properly.  And it's alot of labor, so consider replacing all
6 while you're in there.

I replaced all 6 of mine, so I'd be happy to give you some help if/when you
do yours.

Get a service manual.  Chilton and Haynes are decent, but an OEM shop manual
is better.  It will pay for itself the first time you do a repair yourself.

Bill G
'91 SE Auto
167K Miles

i figured out what the flutter noise was, i have a small exhaust leak.
thanks for all your help