Thank you so much for posting the above situation and the subsequent response!
I have a 1998 Saturn (82,000 km) which displayed symptoms similar to the above; it would start easily in the morning and at the end of the workday, it would run well for about 5 minutes then warning lights wOuld flash briefly and sometimes it would buck and it would turn itself off -sometimes while driving (and I would coast to a stop) and sometimes at a stoplight. After this type of episode, it was difficult to restart.
I took it to the mechanics twice and their computor indicated nothing wrong. They drove it four times and the car behaved well for them.
For me the car continued to stall out. I googled and found the above situation and recommendation.
I called the mechanic again - told them the car continued to stall for me and it was getting worse. I requested they replace the crank shaft sensor; They stated they would consider it and to bring it in again.
My car finally displayed its symptoms in their Shoppe and the mechanic was able to capture the situation on their computor.
They replaced the Crank Sensor and the Idle Air Control Motor.
Since then, the car has been behaving beautifully! (And I am pleased I do not have to think about getting a new car yet)
HAPPY NEW YEAR!
Saturday, January 1st, 2011 AT 6:14 PM