EVIL ENERGY 0928400535 Diesel Fuel Pressure Regulator Compatible with 2001-2004 6.6L LB7 Duramax Diesel

Tools Required

• Jack and jack stands
• Wrench set (do NOT use adjustable wrenches)
• AN-6 style fittings and o-rings
• Drill and drill bits (for mounting bracket)
• Fuel pressure gauge (0-100 PSI)
• Thread sealant (for 1/8" NPT gauge port only)
• Shop towels and drain pan
• Safety goggles and protective gloves
• Fire extinguisher
• Fuse puller

Pre-Installation Checklist

• Park vehicle on a flat, well-ventilated surface; post No Smoking signs
• Allow engine to cool completely before starting work
• Keep fire extinguisher within arm's reach of the work area
• Wear safety goggles and protective gloves at all times
• Open the fuse box and remove the fuel pump fuse
• Start the engine and let it run until it stalls (relieves residual fuel pressure)
• Do not open the fuel system until pressure has been fully relieved
• Disconnect the negative battery terminal
• Do NOT test the regulator with a hand-held air pump — slight leakage through the adjustment screw is normal and does not affect performance

Installation Steps

1. Relieve fuel system pressure: remove fuel pump fuse, start engine to burn off residual fuel, disconnect battery
2. Remove any cosmetic covers to access the fuel pressure regulator area
3. Remove the vacuum line from the OEM regulator (some vehicles do not have vacuum-operated regulators)
4. Place shop towels around the regulator area, remove OEM regulator mounting hardware and fuel lines, then carefully remove the regulator
5. Find a suitable place in the engine compartment to mount the new regulator; use the supplied bracket as a template, mark and drill mounting holes
6. Attach the bracket to the regulator and mount it to the vehicle
7. Attach fuel line(s) from the fuel rail outlet port(s) to the regulator side ports using AN-6 fittings and o-rings; plug unused ports with an AN-6 port plug and o-ring
8. Attach the fuel return line to the regulator bottom port using AN-6 fitting and o-ring; tighten all connections
9. For returnless fuel rail: route fuel into one side port and out the opposite side port to the fuel rail; route a return line from the bottom port back to the fuel tank
10. Install a fuel pressure gauge to the 1/8" NPT gauge port using thread sealant
11. 1Clean up any spilled gasoline and remove soaked shop towels from the work area
12. 1Reconnect battery, turn ignition to ON (do NOT start), check fuel pressure; repeat ON/OFF cycles until gauge registers pressure
13. 1Inspect all fittings, fuel lines, and connections around the regulator for leaks
14. 1Start the engine and adjust regulator to desired fuel pressure — turn clockwise to increase, counter-clockwise to decrease (OEM ~43 PSI without vacuum line)
15. 1Once desired pressure is achieved, tighten the regulator adjustment jam nut
16. 1Connect vacuum line to the regulator (if applicable); if unused, leave vacuum port open to atmosphere
17. 1Test drive and re-check the fuel system for leaks; shut off engine immediately if leaks are found

Post-Installation Verification

• Before starting, inspect all fittings and fuel line connections for leaks
• Turn key to ON (do not start), let fuel pump run to pressurize — repeat 2-3 times until gauge shows reading
• If no fuel pressure, turn key OFF and wait one minute before cycling ON again
• Start the engine; check gauge reading and all connection points for leaks
• Adjust regulator to target pressure (OEM ~43 PSI without vacuum line; adjustment range 30-70 PSI)
• Once at target pressure, tighten the adjustment jam nut
• Attach vacuum line if the vehicle has one; leave vacuum port open to atmosphere if unused
• After test drive, re-inspect all connections for leaks

Troubleshooting

• No fuel pressure: check that fuel pump fuse is reinstalled, verify pump power wiring, repeat ON/OFF pressurization cycles
• Leaking at fittings: shut off engine and relieve system pressure, re-tighten or reinstall the fitting with correct o-rings
• Poor regulator performance with vacuum port blocked: leave vacuum port open to atmosphere — blocking it yields poor results; replace fitting if cracked or broken
• Unstable pressure: check fuel lines for air pockets, verify regulator setting, inspect filters for blockage
• Regulator leaks when tested with hand-held pump: this is normal — slight leakage through the adjustment screw threads is typical and does not affect on-vehicle performance
• DO NOT mount regulator on exhaust manifold or near extreme heat sources

Maintenance

• Visually inspect all fuel line connections every 5,000 miles or at each oil change
• Periodically check regulator mounting bracket for tightness
• Inspect vacuum line connection (if applicable) for cracks or leaks
• Verify fuel pressure gauge reading periodically to ensure stable regulation

Brand Summary

Return Reasons

1. Quality Issues: Provide photos/videos; we cover return shipping.
2. Wrong Item Ordered: Buyer covers return shipping; email within 30 days.
3. Change of Mind: Buyer covers return shipping; email within 30 days.
4. Shipping Damage: Inspect packages; do not sign for damaged items.
5. Incorrect Item Shipped: Contact within 7 days.

Price Protection Policy

Effective from August 25, 2024. Price drops within 7 days of purchase can be claimed.

Disclaimer

EVIL ENERGY reserves the right to interpret, modify, or terminate this policy in accordance with applicable laws and regulations.

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