4C3Z9A543 | Genuine International® High Pressure Oil Pump For Ford 2003-04 6.0L

2003-2004 Ford E-350 Van 6.0L
2003-2004 Ford E-450 Van 6.0L
2003-2004 Ford Excursion 6.0L
2003-2004 Ford F-250 Pickup
2003-2004 Ford F-350 Pickup
2003-2004 Ford F-450 Pickup
2003-2004 Ford F-550 Pickup

1. Power the Injectors (in HEUI Systems)

• The High Pressure Oil Pump (HPOP) creates oil pressure (up to ~3,000 psi).

• That oil pressure drives the fuel injectors, which inject fuel into the combustion chamber.

• Without this pump, the engine cannot inject fuel or run.

2. Enable Precise Fuel Injection

• Electronic control modules regulate injection timing/amount by controlling high-pressure oil.

• This allows for better fuel efficiency, lower emissions, and smoother operation.

3. Cold Start Assistance

• Cold engines require higher oil pressure to fire injectors.

• The HPOP ensures there's enough pressure even during cranking.

4. Supports Emissions Control

• Precise fuel metering via high-pressure injection helps the engine burn cleaner.

• Hard Starting or No Start

  • Cranks, but doesn't fire—especially when cold.

  • Not enough oil pressure to activate injectors.

• Loss of Power

  • Feels sluggish, won’t rev properly, lacks acceleration.

  • Can’t maintain required oil pressure under load.

• Stalling

  • Engine starts but then dies, especially at idle or low RPM.

• Engine Misfires or Rough Idle

  • Inconsistent firing due to poor injector operation.

• Low ICP (Injection Control Pressure) Readings

  • Diagnostic scan shows low pressure from HPOP (even when IPR is commanding high pressure).

• Check Engine Light / Trouble Codes

  • Codes like:

    • P1211, P1283 – ICP out of range

    • P2290, P2291 – Injector control pressure too low

    • P1212 – ICP not at expected level

• Oil Leaks

  • Leaks from the HPOP housing, fittings, or lines.

• High IPR % with Low ICP

  • If the IPR (Injection Pressure Regulator) is near 100% but ICP (Injection Control Pressure) is low, the HPOP is likely failing.