I have a 2001 F250 SuperDuty with a 7.3L powerstroke in it. I'm not a mechanic by any means, but I'm pretty good at taking pictures of stuff. When I cold start the truck, it takes a little too long ~5-7 seconds sometimes to turn over. Then when it does turn over, I have to wait about 5-10 minutes to drive because if I go before then, even pushing the gas pedal down all the way, it barely goes anywhere and can sometimes die. Then when it does catch up on RPM's while driving slowly, it'll go into third but then start to die again. If I let off the gas, there's about a 50/50 chance it'll die or just go really slowly for a time. After it's been running for awhile, it runs just fine. Not sure what's wrong, but I could really use help fixing it. There is an engine code running, it's turbo boost pressure low. Dunno what that means. My father in law says it's probably the timing belt, because those are the same symptoms, but from what I understand, there is no timing belt on a 7.3L diesel because it's all gears. Any help would be greatly appreciated. It's my only way to work and school, and it's the only way to get my wife to her baby doctor appointments. Thanks!

EDIT: Huge thank you to all of you who gave me advice and suggestions. I cold started it this morning and it ran perfectly. I changed the fuel filter, the oil filter, the oil, and the CPS. I'm also going to change the air filter today, and get a new ICP sensor because I'm sure that either has never been changed or has been a long time since it was changed. But again, thank you guys so much for the help!