Hello and welcome to Just Answer, my name is XXXXX XXXXX X will assist you with your question.
Unfortunatly, I am not able to access your prior questions so I will need you to give me some information so that I can help you. I can tell you that in most instances a lack of power will either be a boost or low fuel pressure issue. I will guess that you have had all the common repairs done (hp oil leaks fixed, FICM repaired/replaced and possibly egr and eot coolers and head gaskets performed). If there are any codes stored, please list them for me as well. I will also ask you to give me the complete VIN of the vehicle so that I can research it on Ford's database as well. I will also need to know any modifications done to the truck and if it has a aftermarket fuel tank and what body style the truck is (flat bed, dump, etc), the more info, the better.