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Home >> Ford >> 2003 >> Excursion 7.3 F, RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System & Component Testing - 7.3L Diesel >> Hard Start/No-Start Diagnostic Procedures >> Injection Control Pressure Leak Test >> Left Cylinder Head Check
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Left Cylinder Head Check

  1. Remove cap and plug from high pressure hose for right cylinder head and reinstall hose. Remove high pressure hose from left cylinder head using quick disconnect tool. Using fuel/oil/turbo protector cap set, install appropriate cap on high pressure hose fitting on cylinder head. Install ICP adapter from oil high pressure leakage test adapter set into high pressure hose. See Fig 1.
    Fig 1: Locating High Pressure Hose (Left)
    G99A02508Courtesy of FORD MOTOR CO.
    WARNING: In the following steps, engine may start.
  2. Remove ICP sensor and install sensor in end of ICP adapter. Connect ICP/EBP Adapter Cable (D94T-50-A) between ICP sensor and sensor wiring harness connector, if available. See Figure. If ICP/EBP adapter cable is not available, go to next step. Connect a DVOM between SIG RTN circuit (Black wire) and ICP signal circuit (Green wire) at ICP/EBP adapter cable. Observe DVOM and crank engine. If engine starts, or voltage reading is 1-4 volts, an injection control pressure oil leak exists in left cylinder head. Go to step  4. If engine does not start, or voltage reading is not 1-4 volts, go to step  5.
  3. Using scan tool, access and monitor ICP PID from PID/DATA MONITOR & RECORD menu. Crank engine. If engine starts, or if ICP PID reading indicates 500 psi (3448 kPa) or more, an injection control pressure oil leak has been isolated to the left cylinder head. Go to next step. If engine does not start, or ICP PID is still less than 500 psi (3448 kPa), go to step  5.
  4. Reconnect high pressure hose to left cylinder head. Remove left valve cover. Crank engine, and inspect injector body and injector bore area for oil leakage. Repair as necessary.
  5. If injection control pressure is still low after completing both right and left cylinder head checks and no oil leaks have been found, remove high pressure hose from right and left cylinder heads. Using fuel/oil/turbo protector cap set, install appropriate cap on high pressure hose fitting for each cylinder head.
  6. Using oil high pressure leakage test adapter set, install plug into each high pressure hose. Both high pressure lines should now be blocked off (high pressure pump effectively dead-headed). Using scan tool, observe ICP PID reading while cranking engine. If ICP PID reading is still less than 500 psi (3448 kPa), replace Injection Pressure Regulator (IPR) with a known-good IPR and retest. If ICP PID reading is now 500 psi (3448 kPa) or more, replace IPR. If ICP PID reading is still less than 500 psi (3448 kPa), problem is most likely a faulty high pressure pump or high pressure pump drive gear. Repair as necessary.
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