Im having trouble with my 3SGE idling. However it only has this issue once the engine is at operating temperature and allows the engine to drop below 1000rpm to idle properly. Once it does this the engine chokes (engine light comes on) the engine quickly adjusts and revs back up and then allows itself to drop again resulting in the same problem...this is continuous once warm. If driving the car it is fine no issue, only when it tries to idle.
 
This is a video i took of what the idle up valve was doing that was resulting in choking. 
http://www.youtube.com/watch?v=h_ufVMqz6gs
 
Would this be a faulty Idle Air Control Valve solenoid issue?
 
Any/all help would be greatly appreciated!

"Idle up valve??"
My car is a gen2 3SGE and that looks like a gen3 that is slightly different.
But the video looks like the ACIS butterflies opening and closing. (not an idle up valve BTW).
There is a vacuum switch (VSV) below the intake manifold near the vacuum tank that controls the butterfly actuator.
With motor stopped the butterflies should be open but with the motor running they should close, and then only open above about 5k RPM to effectively shorten the intake runner length at higher revs.
You may have to consult a service manual to troubleshoot the problem.

Sorry i muddled what i was trying to say. I knew that what was shown in the video is an actuator for the ACIS which is controlled by the VSV for Idle up (according to Toyodiy). From what it appears the engine goes to sit at idle but then is unable to and begins to stall. At this point the ECU opens this actuator to raise the rpm to stop it from stalling.
 
If this is a VSV issue. Could the vacuum tank cause this? As it is the only part i have needed to replace in the system. Possibly faulty? The only other thing i could think of is the IACV that sits under the throttle body.
 
Thanks for replying 

From what I have read on it I did not think it had much to do with idle up but I am definitely not an expert lol.

BTW I should mention that on my car to access the VSV you can only get at it from under the car, just forward of the rear X member on the passenger side of the exhaust pipe.
One of the joys of owning an MR2 lol.
You could try disconnecting the connector to it to see if the pulsing stops. The service manual has a procedure to test the VSV.

Great! Ill give it a go. Thanks for your help. 
 
Luckily i have my own vehicle lift as i learnt how difficult it is to work on these cars when on your back.

Good luck, and post up how you get on.

Okay so i believe i have got it all sorted out now. It seemed to be quite a few issues, first being the ignitor and coil pack. 
 
Having a hunch that it would possibly relate to the IACV. I whipped off the IACV to find that the rear seal had slightly been damaged, the inside valve had a fair bit of resistance and there was a slight bit of corrosion which cleaned up easily. At the same time i replaced the solenoid with a spare one i had from a turbo. 
 
 
Cleaning this up and replacing parts helped the issue slightly but due to now having an air pocket in the coolant system the issue was still prevalent. Bleeding the system a few times made a big difference the issue wasnt happening as much. 
 
Lastly it turned out that the engine builders put the vacuum lines on the wrong spots. So the Fuel pressure VSV was flowing into where the ACIS vacuum tank line should of been flowing to and visa versa. Its now not having any issues with the actuator going mental and the engine running rich.
 
Time will tell when i take her for a proper drive tomorrow.
 
Cheers again for helping

"Lastly it turned out that the engine builders put the vacuum lines on the wrong spots. So the Fuel pressure VSV was flowing into where the ACIS vacuum tank line should of been flowing to and visa versa. Its now not having any issues with the actuator going mental and the engine running rich".

That would be the main cause of the problem, the IACV and ACIS are two separate independent systems.
 
 
 

Turns out that it didnt fix it....in fact its worse now, to the point that it stalls itself. Though it worked flawlessly last night. Im quite stumped at the moment. Suppose testing the VSV itself is the next step. 

Have you reset the ecu after making these changes/repairs?
Its unlikely to help but you never know.