2004 Explorer Edie Bauer "wrench" light and message in "safe mode".

2004 Explorer Edie Bauer I was at highway speed engine faltered hard and noticed the "wrench" light and message in "safe mode". engine was rough for a bit than seemed to return to nomal. About 2 miles later the engine fasltered and stalled. I was able to start again smae warning lights with the "service engine" light now on as well. I got maybe another half mile and stalled again. Same warning light biut this time I was not able to start - engione would start to turn over then stop. Had to get a tow.

any ideas?