Bosch VP 44 Diesel Pump

You are reading just the article if you are looking to get a new injection pump for your Dodge Cummins diesel engine but are confused with the available models. This article will take you through some of the common failures of injection pumps. All the Dodge Cummins engines manufactured from 1998 to 2002 had the Bosch VP 44 diesel pump. Sadly enough, these injection pumps had a number of issues and you may have to replace it.

The 4 basic functions of the Bosch VP 44 diesel pumps:

1. Distribution of the high pressure fuel to every cylinder at the correct time.

2. Making sure the exact desired amount of fuel is injected at each cycle.

3. Making sure the time varies depending on the speed of the engine.

4. Production of the high pressure for the fuel which is essential for injection at each cycle.

The Bosch VP 44 diesel pump is an electronic rotary distributor and it varies time of injection and fueling. It also contains data regarding timing, fueling and diagnostics.

The major reason why the Bosch VP 44 diesel pump failed is due to the malfunctioning of the lift pump resulting in a drop in the pressure of the fuel line. Normally, the fuel pressure remains around 15 psi and pump failure happens when it drops to less than 5 psi. A malfunctioning lift pump will usually go unnoticed until it ends up in a costly damage to your Bosch VP 44 diesel pump.

Here are 2 common mechanical failures of the Bosch VP 44 diesel pump:

1. Engine Code 216 – this is quite a common failure and occurs over some time due to weakening lift pumps and low pressure of fuel end up rupturing the diaphragm that is located at the front of the Bosch VP 44 diesel pump. This results in the timing piston vibrating so much that it wears out the pump’s housing and allows the fuel to bypass the piston. Dodge has realized this issue and has stopped selling the pump that is on the side of the block replacing it with a tank mounted unit instead.

2. Seizure of the Rotor – this is another common failure with the Bosch VP 44 diesel pumps and happens when the rotor in the pump’s distribution section seizes. Lack of lubrication is the main reason for this rotor seizure. The injection pumps of the Bosch are lubricated by fuel, so this failure is due to weakening of the lift pumps. This seizure then breaks the drive plate stopping your truck from starting till you replace the Bosch VP 44 diesel pump!
How to prevent the failure of the Bosch VP 44 diesel pump?

The only way to avoid any failure of your Bosch VP 44 diesel pump is to prevent it from occurring. Purchase a replacement lift pump that is a better quality than the one that comes fitted from the factory as the first step. If this is not in your budget right now, installing a gauge that can monitor the fuel pressure should be helpful. The gauge will warn you whenever there are signs of the lift pump going out allowing you to fix the problem before you lose the Bosch VP 44 diesel pump.