rough idle and stalling mid-turns

Hi Guys,

A few times this winter, including last night, now and then as I'm sitting at a light the car starts idling very rough. It dips down to 100, spudders, shakes violently, zooms back up to 1000, dips down again.. and now and then stalls. If I catch it and throw it in nuetral and rev the gas of course I can keep her going. It's also stalling on me while making turns. Starts right back up with no problems but it's a bit of a concern. I didn't notice it last night till I realised the stearing wheel wouldn't move, started it right back up while the car was still moving.
Can you give me some ideas as to why it would idle so rough, and die, when making turns (clutch in, I assume it gets down real low at this point)?
My car is a 91 240sx.

clean AICV, see if it helps.

Hi Jay, thanks but I don't know what aicv is, do you mean the idle air control valve?

yes.

yeah, I just type fast, so typos occur.

Thanks