Date registered: Apr 2012
Mentioned: 0 Post(s)
Quoted: 0 Post(s)
Misfire after first starting; you may have one or more check valves in the injection pump not holding pressure and bleeding down while shut off. It takes a little bit for the pump to repressurize the line/s where that is happening, so during that time, the engine idles a little rough as one or more cylinders isn't getting fuel.
To check for that, once the engine is idling smoothly, turn off the engine and re-start it after a short pause. The check valves will likely not have enough time to bleed down much and if you get a smooth idle, you can assume that the lines are staying pressurized.
The bleed down is usually a slow one, since the check valves typically hold some pressure and take a while to lose pressure, sometimes overnight, sometimes after a couple of days.