where is the ignition module on a 2002 s-10 with a 2.2 liter engine?

i'll be driving along when, without warning, the engine stalls out. it happens at all different speeds, sometimes when the engine has been running for 45 min. and sometimes when only running for 5 min. never have less than 1/2 tank of gas. truck has 75000 miles. dealer says o2 sensor, fuel pump, filter, crank position sensor are o.k. doesn't happen every day, just from time to time.