You can have 100+ DTCs without a check engine light. Just because you are seeing a CEL with P0351 and P0356 doesn't mean these two DTCs are more severe and critical than the other 100+ DTCs. To retrieve other non-P DTCs and non-P0xxx DTCs you need a scanner capable to retrieve Ford's specific DTCs, Foxwell NT510 Elite w/ Ford software and OBDLink MX+, a good combo you must buy if you really want to diagnose this yourself. When you see only the two DTCs that indicate you are using a generic scanner, which is next to useless but better than no scanner at all.