DW400 Fuel Pump Module for RSX Civic Install Guide
By DeatschWerks | Published: 2026-10-23
Category: How-to Guides
Step-by-step instructions for installing the DeatschWerks DW400 pump module with CPE return kit on a 7th gen Civic or RSX. Avoid common mistakes and ensure a reliable fuel system upgrade.
Quick answer
Install the DeatschWerks DW400 pump module with CPE return kit as a direct-fit upgrade for your 2001-2005 Civic or 2002-2006 RSX. Follow the steps below to avoid fuel system leaks and ensure proper return line routing.
Why choose the DW400 pump module assembly
The DeatschWerks DW400 pump module assembly is a complete drop-in solution designed specifically for the 7th gen Civic and RSX. It delivers 415 liters per hour, supporting substantial power upgrades without the need for custom fabrication. The included CPE return kit simplifies the conversion from a returnless to a return-style fuel system, which is essential for high-horsepower builds.
Because the module is a direct fit, you avoid the guesswork of retrofitting a universal pump into your factory fuel tank. However, the return kit requires careful routing of the return line back to the tank, and the high flow rate may exceed the capacity of your stock fuel pressure regulator. Plan for an adjustable regulator if your setup demands precise pressure control.
Installation steps
- 1. Disconnect battery and relieve fuel pressure: Remove the negative battery terminal. Locate the fuel pump fuse in the under-hood fuse box and run the engine until it stalls to relieve system pressure. Then disconnect the fuel lines at the pump module access cover. Skipping pressure relief can cause fuel spray when you open the lines.
- 2. Remove the factory pump module assembly: Remove the access cover in the trunk or rear seat area. Disconnect the electrical connector and fuel lines. Use a plastic trim tool to release the locking ring or retaining nuts. Lift the old module out carefully to avoid damaging the fuel level sender. The sender arm is fragile; do not bend it.
- 3. Install the DW400 module into the tank: Lower the DW400 pump module assembly into the tank, aligning the fuel level sender with the factory float position. Ensure the gasket is seated properly. Tighten the locking ring or nuts to the manufacturer's torque specification. A misaligned gasket will cause fuel odor and potential leaks.
- 4. Route the return line from the CPE return kit: Connect the return line from the kit to the module's return port. Run the line along the factory fuel line path toward the engine bay. Use the supplied clamps and secure the line away from heat sources and moving parts. Avoid sharp bends that can kink the hose and restrict flow.
- 5. Connect fuel supply and return lines at the engine: Attach the supply line from the DW400 module to your engine's fuel rail inlet. Connect the return line from the CPE kit to the fuel pressure regulator return port. If using an aftermarket regulator, install it between the rail and the return line. Confirm the regulator is rated for the DW400's flow; otherwise fuel pressure may be erratic.
- 6. Reconnect battery and test for leaks: Reconnect the negative battery terminal. Turn the ignition key to the ON position (do not start) to prime the pump. Inspect all connections for leaks. Start the engine and check again while idling. A small drip at a fitting can worsen under driving vibration; tighten or reseal as needed.
Product facts
- DW400 Pump Module with CPE return kit for RSX/7th Gen Civic: The DW400 Pump Module with CPE return kit delivers 415 liters per hour and is a direct fit for 2001-2005 Honda Civic (7th Gen) and 2002-2006 Acura RSX. This high flow rate supports significant power upgrades, and the direct-fit design means you don't need to modify your fuel tank or hanger assembly.
DW400 Pump Module with CPE return kit for RSX/7th Gen Civic
