Could be a lot of things but I would start looking for any Vac lines that are broken or leaking.

Weak battery? Dying cam sensor?

I had a similar issue! And was the ISC and I never got CEL.
Try this! Let the car idle and turn the AC on or put any load to the engine without revving and if it stalls or the rpm get really low (400-500rpm) the it might me the ISC you can remove it and check the resistance on the coils!

scan for codes if you don't have any it could be a dirty throttle body . try turning the minimum airflow screw out a 1/4 of a turn to see if that helps . that is the screw in front of the throttle body it could have a rubber plug covering it . if that helps then your throttle body is dirty and it doesn't bypass enough air to keep the car running.

Had a similar issue with my 91 GST. My car would randomly rumble and stutter all over itself. The issue ending up being bad caps on ECU. Do you hear any clicking around the radio location when it starts to stumble?

Do a boost leak test.

I have the same issue. mine is the idle air control being bad. doesnt happen everytime, just sometimes

IA/SC (idle air/speed control .. however the user describes it ...I call it an ISC..) prevents the stalling.

Unit needs to be reset, or replaced.

rumbling? may be the clutch still slightly engaged, did you push it all the way down? if so, may need to be adjusted a little.

is it overheating at all?

Yeah, like a lot of people said it could be a number of things.
First I would determine whether or not its an electrical issue and go from there.

Does the car Idle at all? And what does it idle at?

Just had that issue and mine was biss and tps out of adjustment.

Before you go replacing stuff, although you MAY need to, do your maintenance first. I would clean throttle body, check all vacuum lines and fix, adjust biss screw, fix boost leaks PROPERLY, also make pcv valve is functional. After all checks out, adjust tps/test or replace. Get black isc.

adjust biss screw

Click to expand...

BUT, before you mess with the BISS screw, reset the ISC unit so the BISS screw can work properly and correctly. vfaq has the procedure on how to do this procedure:

http://www.vfaq.com/mods/BISS-1G.html

Good luck - DSM

Did you ever get this resolved? I had this problem but it would only stall when I had the AC on a hot summer day when it was 100+ if I didn't have the AC on it would idle fine and not stall.

Has this problem ever been solved? Every thread I see it doesn’t seem like anyone came back from this and it’s happening to me.