Fuel Pressure on 1998.5-2002 Dodge Cummins 24v 5.9L

One of the most important items to check regularly on your Dodge Cummins 24v 5.9L engine is the fuel pressure from the electric fuel supply pump. This is extremely important on the 1998.5-2002 year model vehicles. Failure to keep the VP44 injection pump supplied with the correct amount of fuel pressure will cause the injection pump to fail which can result in a major repair bill. The pressure needs to be no less than 7-8 psi when under a heavy load or hard acceleration condition. New supply pumps (see picture) will usually put out about 14 psi @ idle & then drop to 7-8 psi under a load. Here are a couple different ways to check the fuel pressure on the 1998.5-2002 vehicles. When checking the fuel pressure you need to make sure that you check it before the fuel filter & after the fuel filter. Checking it at these 2 locations will let you know what kind of pressure drop to expect after the fuel filter. On the early 1998.5-1999 year model Dodge Cummins diesels there are 2 brass fittings on top of the fuel filter canister. One fitting is for checking pressure before the filter & one is for checking pressure after the filter. On the 2000-2002 year model vehicles, there is really only 1 fitting in the system that is easy to use & it is located at the inlet of the injection pump. The fitting at the pump has a schrader valve in it so all you need to do is connect a hose with the correct size of fitting on it & start the engine. Fuel pressure test kits are readily available at various internet performance web sites. Monitoring the fuel pressure on the vehicle can be done a couple different ways. One way is to install a warning light that will come on when the fuel pressure drops below 5 psi. Another way is to install a fuel pressure gauge. Depending on how your vehicle is set up, whether or not you have a performance chip, injectors or if your vehicle is stock if you do not check or monitor the fuel pressure you will have to replace the injection pump.