I would also check the timing... on my car the timing some how got really far advanced and ran like $h!t

 

Early models used an actual motor actuator to physically move the throttle plate open or closed as a means of adjusting idle- It was called an ISC/MPS or Idle Speed Controller with a Motor Position Sensor. If the setting of the MPS is off- it can cause idle hunting as if someone was stepping on the throttle and letting it go. I have seen many instances where someone turned a screw here or touched an adjustment there throwing EVERYTHING off. It may not need a single thing at this time- it may just need to be adjusted PROPERLY.
Later models used an IAC to control idle with basically allows a controlled amount of air to bypass a fully closed throttle plate.

Joel, CA

 

Ah O.K. I didn't know they used the ISC on the 1g's my bad.

 

Not ALL 1G's used the ISC setup- my 93 DOHC has a IAC but i'm not exactly sure what year they started with it.

Joel, CA

 

I'll browse around through a few books I have and see if I can find something that tells what year and what engine they started the IAC with.