I have had poison ivy, all lesions healed and gone, then a itching and flaming red skin started on hands and feet, legs, butt, not external.

Different cause. You're itching at this point is probably not related to the poison ivy.You should see a medical doctor since there can be internal causes of pruritus better known as itching.
Repeat contact. The most likely cause is continuing contact with the poison ivy resin left on your clothing, shoes, car seats etc. You need to wash them all out with a laundry detergent. A less likely cause is a secondary bacterial infection from scratching the areas.