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Engine Controls - System & Component Tests - 7.3L Diesel: Other Ford Pickup F350

Testing & Diagnostics 3 illustrations ~1496 words

CHECK FOR CODES

If steps under QUICK TEST in TESTS W/CODES - 7.3L DIESEL article have been successfully completed, and a Code P1111 (system pass) is present, go to CHECK PARAMETER IDENTIFICATION (PID) DURING CRANKING. If QUICK TEST has not been completed, perform QUICK TEST. If any trouble codes are present, service codes as necessary.

Right Cylinder Head Check

  1. Perform step 4) under CHECK PARAMETER IDENTIFICATION (PID) DURING CRANKING (if not already completed). Remove high pressure hose from right cylinder head. Using Fuel/Oil/Turbo Protector Cap Set (T94T-9395-AH), install appropriate cap on high pressure hose fitting on cylinder head. Using Oil High Pressure Leakage Test Adapter Set (D94T-6600-A), install plug into high pressure hose. WARNING: In the following step, engine may start.
  2. Install ICP/EBP Adapter Cable (D94T-50-A) between ICP sensor and sensor wiring harness connector. 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. Voltage reading should be 1-4 volts.
  3. If engine starts, or if ICP PID reading indicates 500 psi (33448 kPa) or more, an injection control pressure oil leak exists in right cylinder head. Inspect fuel system for oil contamination.
  4. If no oil is present in fuel system, remove cap and plug, and reinstall high pressure hose to right cylinder head. Remove right valve cover. Crank engine, and inspect injector body and injector bore area for oil leakage. Repair as necessary. If engine does not start, or ICP PID is still less than 500 psi (3448 kPa), perform «LEFT CYLINDER HEAD CHECK»(ref-23714-S42928921772001010300000) .

Left Cylinder Head Check

  1. Remove high pressure hose from left cylinder head. Using fuel/oil/turbo protector cap set, install appropriate cap on high pressure hose fitting on cylinder head. Using oil high pressure leakage test adapter set, install ICP adapter into high pressure hose. (Scheme 409)
  2. Remove ICP sensor and install sensor in end of ICP adapter. Install ICP/EBP Adapter Cable (D94T-50-A) between ICP sensor and sensor wiring harness connector. 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. Voltage reading should be1-4 volts. WARNING: In the following step, engine may start.
  3. If engine starts, or if ICP PID reading indicates 500 psi (3448 kPa) or more, a injection control pressure oil leak exists in left cylinder head. 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.
  4. 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 on each cylinder head.
  5. Using oil high pressure leakage test adapter set, install plug into each high pressure hose. Both high pressure lines should now be blocked off. Using scan tester, observe ICP PID reading while cranking engine.
  6. If PID reading is still less than 500 psi (3448 kPa), replace Injection Pressure Regulator (ICP) with a known good ICP and retest. If PID reading is now 500 psi (3448 kPa) or more, replace ICP. If PID reading is still less than 500 psi (3448 kPa), high pressure pump or high pressure pump drive gear is faulty. Repair as necessary.

Scheme 409

Scheme 409
Scheme 409

Check Air Filter

Inspect air cleaner assembly for proper installation. Ensure air ducting is not blocked or collapsed. Inspect filter minder on filter housing to ensure intake restriction is below Red marks. Replace filter as necessary.

If steps under QUICK TEST in TESTS W/CODES - 7.3L DIESEL article have been successfully completed, and a Code P1111 (system pass) is present, go to TANDEM FUEL PUMP PRESSURE TEST . If QUICK TEST has not been completed, perform QUICK TEST. If any trouble codes are present, service codes as necessary.

CHECK FOR AIR IN FUEL SYSTEM

  1. Disconnect fuel return hose at fuel filter. Install a clear fuel hose between fuel return hose and fuel return hose fitting at fuel filter. Loop hose at a point higher then fuel filter. (Scheme 410) While observing fuel line, start and run engine for about 5 minutes. Fuel should be free of air.
  2. If fuel is foamy, check for an air leak in fuel lines between fuel pump and fuel tank. Repair as necessary. If no fuel flow exists, remove fuel regulator block, taking care not to damage "O" ring. Inspect fuel strainer assembly (1995 models only) and fuel return orifice screen for debris. Clean as necessary. (Scheme 411)

Scheme 410

Scheme 410
Scheme 410

Scheme 411

Scheme 411
Scheme 411

Oil Aeration/Poor Idle

  1. Connect New Generation Star (NGS) tester to Data Link Connector (DLC). Turn A/C off. Using scan tester, access ICP PID from PID/DATA monitor menu. See ADDITIONAL SYSTEM FUNCTIONS in the «TESTS W/CODES - 7.3L DIESEL»(ref-23600) article.
  2. Start engine and hold at wide open throttle for one minutes. ICP PID should be 1100-1750 psi (7585-12066 kPa). If ICP PID reading increases to more than 1750 psi (12066 kPa) after one minutes, anti-foam additives may have become depleted from oil. Change oil and retest.

Low Idle Stability (ICP Pressure)

  1. Ensure engine is at normal operating temperature. Using scan tester, access ICP PID from PID/DATA monitor menu. Start engine and allow it to idle.
  2. ICP reading should be 550-700 psi (3792-4826 kPa). If PID reading is not 550-700 (3792-4826 kPa), or idle does not stabilize, disconnect ICP sensor. Sensor is located at top left side of engine.
  3. If idle is now stabilized, fault is in ICP sensor circuit. Perform CIRCUIT TEST Z in «TESTS W/CODES - 7.3L DIESEL»(ref-23600) article. If idle still does not stabilize, change Injection Pressure Regulator (IPR) and retest.

CHECK CYLINDER PERFORMANCE

If KOER CYLINDER CONTRIBUTION SELF-TEST under QUICK TEST in the TESTS W/CODES - 7.3L DIESEL article has been successfully completed previously, go to CHECK FOR EXHAUST RESTRICTION. If KOER CYLINDER CONTRIBUTION SELF-TEST has not been completed, perform KOER CYLINDER CONTRIBUTION SELF-TEST. Possible causes for failing this test are

  1. Broken compression rings.
  2. Burnt or bent valve.
  3. Bent push rods.
  4. Bent connecting rods.
  5. Damaged rocker arms.
  6. Faulty fuel injector assembly.

With New Generation Star (NGS) Tester

  1. Ensure engine is at normal operating temperature. Connect NGS tester to Data Link Connector (DLC). Turn A/C off. Using scan tester, access MGP PID from PID/DATA monitor menu. See ADDITIONAL SYSTEM FUNCTIONS in the «TESTS W/CODES - 7.3L DIESEL»(ref-23600) article.
  2. Observe PID reading and road test vehicle. Accelerate vehicle to achieve highest boost level (2500-3500 RPM). Note PID reading. Boost level will level out after 3000 RPM. If PID reading is 16 psi (110 kPa) or more, boost level is okay. If boost level is not okay, see DIAGNOSTIC AIDS.

Without New Generation Star (NGS) Tester

  1. Ensure engine is at normal operating temperature. Disconnect Manifold Absolute Pressure (MAP) sensor hose at intake manifold. Install a "T" fitting between MAP sensor hose and hose nipple at manifold. Connect a 0-30 psi (0-207 kPa) gauge to "T" fitting.
  2. Ensure hose is long enough so gauge can be put inside cab of vehicle. Road test vehicle. Observe pressure gauge and accelerate vehicle to achieve highest boost level (2500-3500 RPM). Note pressure reading. Boost level will level out after 3000 RPM. If boost pressure is 16 psi (110 kPa) or more, boost level is okay. If boost level is not okay, see DIAGNOSTIC AIDS.

No Boost

  1. Wastegate actuator not functioning. See appropriate SELF-DIAGNOSTICS article.
  2. Compress air intake hose collapsed. Repair or replace as required.
  3. Compressor manifold hoses leaking. Tighten hose clamps.
  4. Turbocharger turbine or compressor wheel damage. Replace turbocharger.
  5. Turbocharger bearings seized. Replace turbocharger.
  6. Clogged air cleaner element or restriction upstream of compressor. Repair or replace as required.

Lack Of Power

  1. Low compression. Repair as required.
  2. Wastage actuator not functioning. See appropriate SELF-DIAGNOSTICS article.
  3. Clogged air cleaner element or restriction upstream of compressor. Replace the air cleaner element. Remove the restriction.
  4. Insufficient fuel supply. Repair or replace as required.

Excessive Fuel Consumption (Black Exhaust Smoke)

  1. High fuel pressure or pressure regulator. Repair as required. For more information, see appropriate SELF-DIAGNOSTIC article.
  2. Fuel return line plugged or kinked. Clean or replace as required.
  3. Injectors leaking. Replace injectors.
  4. Powertrain control module malfunctioning. See appropriate SELF-DIAGNOSTICS article.

Excessive Oil Consumption (Blue, Gray Or White Exhaust Smoke)

  1. Incorrect type or grade of oil. Drain and fill with specified oil.
  2. Extended oil change intervals. Change oil as recommended.
  3. Clogged air cleaner element or restriction upstream of compressor. Repair as required.
  4. Engine wear (piston rings, valve guides). Repair as required.
  5. Turbocharger oil seals leaking. See «TURBOCHARGER INTERNAL OIL LEAK TEST»(ref-23714-S42045689512004022600000) under COMPONENT TESTS.
  6. Injector or injector "O" ring leaking. See appropriate SELF-DIAGNOSTICS article.

High Boost

  1. Leak in exhaust system before muffler. Repair as required.
  2. Malfunctioning wastegate. See appropriate SELF-DIAGNOSTIC article.

Bearing Clearance Check

For bearing clearance check, see TURBOCHARGER OVERHAUL under FUEL SYSTEM in REMOVAL, OVERHAUL & INSTALLATION - TRUCKS - DIESEL article.

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