Without the oil embargo the Japanese would not have faced the stark choice of withdrawing from conquered territory or watching their militray machine and their economy both collapse as oil ran out. So there is a decent chance the Japanese would not have attacked the US in 1941
It may be, though, that the entry of the Flying Tigers into combat in 1942 would have caused the Japanese to go to war with America absent an embargo. The first group of US fighter pilots and ground crew were already in Burma by December 1941. Not always noticed is that a second group of of volunteers assembling in the US consisted of BOMBER crews, and that they and their planes would be leaving US ports in December 1941.
FDR was either bold (my view) or reckless in being as unneutral as he could get away with being in 1941 vis a vis the Axis powers. I wonder how far the American Volunteer Group would have been allowed to go, given time, in taking the war to Japan in 1942. Would FDR have followed up shipments of Lockheed Hudsons and DB-7s in Decemebr 1941 with B-17s or B-24s in 1942? Was he going to push the Japanese until they attacked the US?