PureFlow AirDog 98.5-04 Dodge 24V 5.9L Cummins (w/Fuel Pump) FP-100-4G Fuel Air Separation System
This is the AirDog FP-100-4G, part A4SPBD153, for 1998.5-2004 Dodge Ram 5.9L 24-valve Cummins trucks that have an electric fuel pump inside the tank. If your VP44 truck cranks long, falls on its face under load, or you simply want to stop starving the injection pump, this kit puts a frame-mounted lift pump, water separator and 2 micron filter between the tank and the engine.
The VP44 rotary pump on 1998.5-2002 trucks and the early CP3 on 2003-2004 trucks both rely on steady supply pressure. The FP-100-4G pulls fuel through a water separator, pressurizes it with a gerotor pump and pushes it through a 2 micron filter straight to the injection pump. It skips the factory filter housing. Air and vapor go back to the tank through a tee in the filler neck. This is the Original AirDog design, rated at 100 gallons per hour, and the right size for a stock or mildly tuned truck.
An in-tank pump would be pulled against by the AirDog and wear out quickly. To prevent that, this kit includes the WAP109 high-flow draw straw. It goes into the top of the tank through a 1 inch hole, so the AirDog draws fuel directly and bypasses the factory in-tank pump. AirDog says skipping the straw or a sump will cause pump failure. If your truck still uses the engine-mounted lift pump, buy the FP-100-4G without in-tank pump instead.
Put a gauge on the supply side at the injection pump and watch it at idle and under load. If pressure drops while the engine is working, the supply side is the problem. Check whether the truck has an in-tank pump. Many 24-valve trucks got one from a dealer update or a previous owner. If you are diagnosing a towing complaint, our 47RE overheating guide covers the transmission side of the same truck.
AirDog lists A4SPBD153 for 1998.5, 1999, 2000, 2001, 2002, 2003 and 2004 Dodge/Ram 5.9L Cummins with a factory or retrofitted in-tank fuel pump. The kit includes supply-line instructions for both VP44 and CP3 trucks. The 2004.5 and later trucks use a different kit. If you need more flow for larger injectors, use the FP-150-4G for the same trucks. Not sure what is in your tank? Send us the year and VIN. These trucks run the 47RE or 48RE transmission, and we stock both.
| Brand | AirDog |
| Part number | A4SPBD153 |
| Fits | PureFlow AirDog 98.5-04 Dodge 24V 5.9L Cummins (w/Fuel Pump) FP-100-4G Fuel Air Separation System |
| Type | Fuel Air Separators |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
Look for the factory electric lift pump on the engine block, below and behind the filter housing. If it is gone or disconnected and the tank sending unit has a pump wired to it, you have an in-tank pump and this A4SPBD153 kit is the right one.
Yes, or you can remove the bed. The WAP109 draw straw goes through a 1 inch hole drilled in the top of the tank, and that is how this version bypasses the in-tank pump.
AirDog presets this application at 15-17 psi. The Original AirDog uses a fixed ball and spring regulator, so changing pressure means installing a different spring from AirDog.
Yes. The kit covers 1998.5-2004 5.9L 24-valve trucks, and the manual has a separate supply-line section for the 2003-2004 CP3. Removing the factory filter housing on those years needs a filter bypass.
AirDog gives typical fuel filter life as 15,000-20,000 miles depending on fuel quality. Replace the water separator every other filter change and drain it about every three months.
