Engine Controls - Basic Diagnostic Procedures - Diesel Ford Econoline I

INTRODUCTION

Note. References to Econoline include Cutaway and RV Cutaway. References to Pickup include Cab & Chassis.

The following diagnostic steps will help prevent overlooking a simple problem. This is also where to begin diagnosis for a no-start condition.

The first step in diagnosing any driveability problem is verifying the symptom(s) with a test drive under the conditions the problem reportedly occurred.

Before entering self-diagnostics, perform a careful and complete visual inspection. Most engine control problems result from mechanical breakdowns, poor electrical connections or damaged/misrouted vacuum hoses. Before condemning the computerized system, perform each test listed in this article.

VISUAL INSPECTION

Visually inspect all electrical wiring, looking for chafed, stretched, cut or pinched wiring. Ensure electrical connectors fit tightly and are not corroded. Ensure vacuum hoses are properly routed and are not pinched or cut. Inspect air induction system for possible vacuum leaks.

Compression

Perform KOER CYLINDER CONTRIBUTION SELF-TEST under QUICK TEST in SELF-DIAGNOSTICS - EEC V - DIESEL article. Service any DTCs that are present. The following are possible causes for failing this test

1. Broken Compression Rings
2. Burnt Or Bent Valves
3. Bent Push Rods
4. Bent Connecting Rods
5. Damaged Rocker Arms
6. Faulty Fuel Injector Assembly

Exhaust System Backpressure

Connect scan tool. Start and run engine until a temperature of 170°F is reached. Disconnect engine oil temperature sensor. Run engine at wide open throttle and monitor EBP PID on scan tool. If pressure exceeds 34 PSI at 3400 RPM, exhaust system is restricted.

PRELIMINARY CHECKS

Ensure following systems and components are in good condition and operating properly before diagnosing problems in fuel injection system

1. Check battery and charging system condition.
2. Check all wiring and vacuum connections.
3. Check air cleaner and ducting.
4. Check state of tune.
5. Check fuel delivery system.
6. Check cooling system.
7. Check inertia fuel shutoff switch.
8. Check for blown head gasket (liquid in cylinder).
9. Check fuel tank contents and fuel gauge accuracy.
10. Check for dirt, water or other contamination in fuel.
11. Check fuel lines and fittings for leaks.
12. Check fuel delivery system for proper pressure and volume.
13. Check for inoperative fuel injectors.
14. Check for improperly installed electronic equipment such as anti-theft system, CB radio, cellular telephone or stereo.

Engine Does Not Crank

Check for enabled anti-theft system. Check starting and charging system for correct operation. Check for hydrostatic lock (liquid in cylinder). Repair as necessary.

Engine Cranks But Will Not Start

1. Check fuel tank contents and fuel gauge accuracy. Check for dirt, water or contamination in fuel.
2. Check fuel lines and fittings for leaks. If no leaks are found, check fuel delivery system for proper pressure and volumes. Reset Inertia Fuel Shutoff (IFS) switch (if necessary).
3. Check for damaged or contaminated fuel injector wiring harness and connector. Ensure fuel injectors pulse when engine is cranked.
4. Check glow plug system. See appropriate SYSTEM TEST in SELF-DIAGNOSTICS - EEC-V - DIESEL article.

FUEL SYSTEM PRESSURE RELEASE

FUEL PRESSURE

Electric Fuel Pump Inlet Restriction

1. Ensure fuel tank has fuel. Ensure fuel pump has power and ground. With ignition on, battery voltage should be present at fuel pump for about 20 seconds. If voltage is as specified, go to next step. If voltage is not as specified, perform TEST FK: FUEL PUMP MONITOR CONTROL under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - DIESEL article.
2. Remove fuel line to inlet side of fuel pump. Install Fuel Pressure Adapter (014-00931-2) between fuel inlet line and fuel pump. Connect fuel pressure adapter to vacuum gauge (0-30 in. Hg) of Engine Pressure Tester (014-00761).
3. Measure restriction at wide open throttle with shift lever in Neutral , brakes set and wheels blocked. If restriction measures more than 6 in. Hg, a blockage exists between fuel pump and fuel tank.

Electric Fuel Pump Pressure Test

1. Remove fuel line from outlet side of fuel pump. Install fuel pressure adapter between fuel outlet line and fuel pump. Connect fuel pressure adapter to 0-160 psi (0-1103 kPa) gauge at engine pressure tester. Run engine at idle and check for leaks from line to gauge. Measure fuel pressure with full load on engine. If fuel pressure measured is less than specified, check fuel regulator valve for debris. For fuel pressure specifications, see appropriate FUEL PRESSURE SPECIFICATIONS article.
2. If fuel regulator is clear, replace electric fuel pump. After replacing fuel pump, recheck fuel pressure to verify that a restriction downstream of pump is not causing high fuel pressure which will cause pump to fail again.

Fuel Pressure Test

1. On Econoline, remove doghouse cover and remove 1/8" inch pipe plug from top of left head. On Excursion and Pickup, remove 1/8" inch pipe plug from top front of right head. On all models, install Gauge Bar (014-0061). Run engine at idle and check for leaks from line and gauge. Measure pressure with full load on engine. If pressure is not as specified, replace fuel filter. For fuel pressure specifications, see appropriate FUEL PRESSURE SPECIFICATIONS article. Recheck fuel pressure, if fuel pressure is still less than specification, replace left head check valve on Econoline or right head check valve on Excursion and Pickup. Check valve is located between fuel inlet line and cylinder head.
2. On Econoline, remove alternator and bracket if necessary. Remove 1/8" inch pipe plug from top front of right head. On Excursion and Pickup, remove 1/8" inch pipe plug from top rear of left head. On all models, install Gauge Bar (014-0061). Run engine at idle and check for leaks from line and gauge. Measure fuel pressure with full load on engine. If fuel pressure is not as specified, replace right head check valve on Econoline or left head check valve on Excursion and Pickup. Check valve is located between fuel inlet line and cylinder head. For fuel pressure specifications, see appropriate FUEL PRESSURE SPECIFICATIONS article.

FUEL INJECTORS

Fuel Injector Checks

Fuel injector resistances are not available. For injector and injector circuit tests, see KOEO INJECTOR ELECTRICAL SELF-TEST under QUICK TEST in SELF-DIAGNOSTICS - DIESEL article.

INERTIA FUEL SHUTOFF SWITCH

1. In event of a collision, electrical contacts in inertia switch open, automatically shutting off fuel pump. Fuel pump shuts off even if engine does not stop running. Engine will stop due to lack of fuel.
2. Engine cannot be restarted until IFS switch is manually reset. To reset IFS switch, depress button on switch located behind right kick panel.

NO-START DIAGNOSIS

Note. No-start is defined as engine cranks okay, but does not start. Engine may fire a few times.

1. Visual engine and chassis inspection. Loose or leaking fuel supply lines. Kinked or blocked fuel supply lines. Massive fuel or oil leaks. Coolant leaks. Electronic connectors and wiring (particularly camshaft position and injection pressure regulator). Pinched or open MAP sensor hose. Pinched or open intercooler hose.
2. Check engine oil level.
3. Check for intake or exhaust restriction.
4. Check for sufficient and clean fuel.
5. Check electric fuel pump pressure. See «FUEL PRESSURE»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures-diesel__fuel-pressure) .
6. Perform KOEO on demand self-test. See SELF-DIAGNOSTICS - EEC V - DIESEL.
7. Retrieve Continuous Memory DTCs. See SELF-DIAGNOSTICS - EEC V - DIESEL.
8. KOEO injector electrical self-test. See «FUEL INJECTORS»(/ford/econoline/i-1985-2013/remont/testing-diagnostics/#engine-controls-basic-diagnostic-procedures-diesel__fuel-injectors) .
9. Using scan tool, monitor: V-PWR Check system voltage. If system voltage is low, check battery, charging system, and powers and grounds at PCM. RPM Low RPM could indicate a starting/charging system problem. No RPM with engine cranking could indicate a faulty CMP circuit. ICP A minimum of 500 PSI is required before injectors are enabled. No or low oil in reservoir, system leakage, injector "O" rings or faulty IPR could cause pressure loss. Fuel PW Even though a 1-6 millisecond fuel pulse width is shown on scan tool to be sent to IDM, it is possible that IDM did not get signal, due to a fault on CID or FDCS circuits or a faulty IDM.
10. Check glow plug system operation. See SYSTEM & COMPONENT TESTING - EEC-V - DIESEL.

INJECTION TIMING

Injection timing is controlled by Camshaft Position (CMP) sensor and not adjustable.

IDLE SPEED

Idle speed is controlled by Powertrain Control Module (PCM) and is not adjustable. If idle concerns exist, see appropriate SELF-DIAGNOSTICS article. If no DTCs exist, go to appropriate TROUBLE SHOOTING - NO CODES article.

SUMMARY

If no faults were found while performing BASIC DIAGNOSTIC PROCEDURES, proceed to SELF-DIAGNOSTICS in SELF DIAGNOSTICS - EEC-V - DIESEL article. If no trouble codes are found in self-diagnostics, proceed to appropriate TROUBLE SHOOTING - NO CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.

See also:
• FUEL PRESSURE
• FUEL INJECTORS