94 sunbird stalls when stopping

Could be an idle air control problem, or possible vacuum booster trouble, have also seen the baffle broken in the GM tanks and when you brake hard the engine dies. Fill the tank and try it, if it doesn't do it the baffle is bad.

From other posts here and other forums I found : Torque converter clutch not disengaging. Causing stall just like if you failed to push manual clutch petal to disengage it from engine flywheel as you braked. With automatic, apparently, at least this model, it doesn't become locked with high pressure until you get near 40 mph (63 kph). Also apparently only after also reaching normal operating temp. So short trips under 60kph as well as in winter, may be spared this happening. Possible causes are dirty tranny fluid needing changing ; gum varnish build up causing it to stick and not release pressure (which could be self checked for by adding a tranny cleaner to see if improvement after 50 or more kilometers. After this cleaner mileage, if all good, should likely get it flushed, new or filter cleaned, new fluid. If cleaner make no diff, other cause may be electrical switch from brake app not sending signal to tranny solenoid to move lever that unlocks clutch and allows to slide back a bit. Or solenoid is weak, when clutch becomes more tight and locked to prevent slippage at and above 60 kph, solenoid too weak to unlock it. But, I'm amaturely guessing, if it only does this after reaching 60 kph and warmed up, the locking mechanism is not totally free to slide off due to varnish gum buildup. Don't mention this to shop. Put in a cleaner like Seafoam Tranny Tune cleaner. If it improves after driving about 50 kms, you have answer. Then just tell shop you'd like the tranny fluid changed. I guess. ;-) In my case, it stopped sticking after about 30 kms with Seafoam Tranny Tune in. Forums I read said filter rarely needs changing. Since getting one would need special ordering, as well as the pan gasket, I asked them to use the tranny flush machine they had, which puts a tube down in that injects fluid which is caught by tight fitting tube clamped to dip stick tube top. When it doesn't look dirty anymore they stop and adjust level to correct level.