My 2005 ford 6.0 diesel started running ruff when I first crank the engine it in the mornings. This only lasts for about 5-15 seconds then smooths out and idles normally. The warms the engine gets the smoother it runs. This started a little over a week ago. In the past two days it has become extremely hard to start and the engine shakes and knocks pretty hard for about 20 seconds, but today I can't get it to start at all. It tries to crank and fire but shuts off before it can run. Any ideas?

Perform steps in the link below:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-8.html#post1415281