Duramax diesel engine

Just a thought, the pump has a check vale in it that keeps the fuel from draining back when the engine is off. If the check valve is bad, then the fuel drains back and creates an air pocket that doesn't allow it to pump the fuel, basically it create a vacuum lock in the pump so no fuel can get through it. So, you can't rule out the pump completely just because it stays running. Now I know that I'm just a computer tech here and the 6 years of shop foreman as a auto and diesel mechanic don't count, but it's a thought.

Even if the pump works after is started, you cannot be sure the pump is not faulty.
The pump is energised by a solenoid, test the solenoid, if it is faulty replace it.
If solenoid is working and pump is being energised properly (you can test this) then, even if pump works it can jam up each time you stop it, in this case replace the pump.

Sounds like you have a leak in the fuel system.This will cause the pump not to be able to get suction.
there is a big fitting on the right side of engine up front this is the fuel fitting need to check fo vacuum. have you replaced filter??need to be replaced every 15k miles if you have then might have a cut oring

You need to get the air bubble released from the pump so all you need to do is manually open the pump screw and the pump out some diesel which will take care of the starting and jerking problem.

You may also check your inline fuel pump under the truck should also be a water seperator inline with it, should have12volt key on cranking

Hey Semi Expert & Mohammed387, you dont know any thing about diesel engines so don't post any solution which is beyond of your experties. Keep playing with computers and celluler phones. :|

If the injection pump isn't pushing fuel through the lines to the injectors, it may have a faulty solenoid. Listen for a "click" inside the pump when the ignition switch is turned on. No click means the solenoid and/or pump need to be replaced. If it clicks but there's no fuel coming through the injector lines (and the filter and lines are not obstructed), the pump is probably bad and needs to be replaced.

The pump has gone bad and need to be changed

I think ther is a fault in motor ...better check whether the coil burnt or not

Read this posting, the problem may be the optical sensor in the fuel pump unit.

• SYMPTOM: Your 6.5L Diesel stalls just as if someone had reached over and turned off the ignition switch.
• CAUSE: There are two main causes. The first and most common is the PMD (also called FSD). The other possibility is the Optical Sensor located in the pump itself.
• DIAGNOSIS: OR "How do I know what to replace?" Simply put, if your check engine light is not on and you experience stalling, it is a 95+ percent certainty that you need a new PMD. If your check engine light is on, you need to get your codes checked. Auto Zone and others will do this for free. If you ONLY have codes P1216, P1217, 35, 36 or any combination of those, you need just the PMD. If you have codes P0251 or PO370, 17, 18, or any combination of those, you should consider the injection pump suspect.
• So what is this PMD? PMD stands for Pump Mounted Driver. The same part is also called an FSD or Fuel Solenoid Driver. (One is GM terminology, the other Stanadyne terminology). It is a "black box" about the size of a pack of cards mounted on the driver's side of the injection pump.
• !
• Check to be sure your lift pump is running. The lift pump delivers fuel to the injection pump and is located on the frame rail under the driver's seat. The lift pump will NOT cause stalling, but when it goes bad, the injection pump runs hotter which shortens PMD life. See lift pump under products for instructions on checking the lift pump.
• Make sure you have good clean fuel with no water
• For the very thorough individual: Check all electrical connections - battery terminals, engine and body grounds, and all fuel injection pump wiring including the multiple grounds on the intake manifold. With the batteries disconnected open up all connections (including those at the bulkhead) and look for loose or corroded connections, but do not spread open the terminals. Take your time and look carefully for chafed wiring. One connector of particular interest is the large15-way connector near the back of the intake manifold where the main engine harness meets the fuel injection harness which then runs forward under the intake to the injection pump. This connector is commonly the site of severe corrosion, especially in northern states and may cause a variety of intermittent problems.
• Those who are very technical and equipped with the proper tools can perform a couple more steps to ensure that they have correctly identified the issue. If the duty cycle measured at the red closure signal wire (Terminal E at the PMD) is not the same as the duty cycle measured at the light green PCM command wire (Terminal A at the PMD) then the PMD has failed. Because of the difficulty of this step and the fact that this issue is so common, only the most exacting individuals perform it.
• If your truck over-responds to the throttle and revs up very rapidly at only light throttle application, or revs up on its own, internal injection pump wear is almost certainly the cause.
• !