I have a 98 f150 4.6l white/gray smoke only on startup throwing lean codes. coolant level has not dropped. i now have miss fire? .it has been smoking on startup since i got the truck the engine was rebuilt but im not sure buy who was before i got it. any suggestions would be great i have a video on my iphone of what it does on startup but you cant upload videos on here if anybody knows how to get my video up here or some how that would be great.

 

Sounds like your valve stim seals are leaking. Whoever overhauled may not have replaced them. Try to find a product called "AT-205" and add it to your oil. It closes all seals. Very few parts places have it. Try googling it.