You know all the spark plugs didn't fail at once and start working after the engine cools down so that was a waste of money unless they were due to be replaced anyway. The most common cause of stalling while driving is a failing camshaft position sensor or crankshaft position sensor. They often fail by becoming heat-sensitive, then work again when they cool down. Since you didn't list which engine you have I can't tell you which is the most likely suspect. Most of the time the Engine Computer will set a diagnostic fault code indicating which circuit has the problem. Did you read the codes? If so, what are the numbers?
When the engine doesn't start, did you check for spark?
Tuesday, May 14th, 2013 AT 8:27 PM