This could be due to an issue with your valve cover gasket harness. The harness has clips that are made of hard plastic. Over time this can become brittle from heat and age. When the clip come undone it can cause your pickup to have a misfire on an injector, or a starting issue with your glow plugs. This is due to a lack of connection. The fix is to replace the valve cover gasket and harness. This should solve the misfire and your pickup will run as it should. Give us a call and let us take care of you.