Your Vehicle: 2001 Ford Escort ZX2 L4-2.0L DOHC VIN 3
 
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  HC: Fuel Delivery System - Pinpoint Test  
 

HC: Fuel Delivery System

HC: Introduction See: Diagnostic Trouble Code Tests and Associated Procedures\SECTION 5: Pinpoint Tests\HC: Fuel Delivery System - Introduction

HC1 CHECK SYSTEM INTEGRITY

  • Visually inspect the complete fuel delivery system for damage; including fuel lines, connections, relays, fuel tank, fuel pump, fuel pressure regulator, fuel pulse damper and fuel injector areas for leaks, looseness, cracks, kinks, pinching, or abrasion caused by a collision or mishandling.
  • Visually inspect electrical harness and connectors for loose pins, corrosion, abrasion, or other damage from collision or mishandling.
  • Check electrical connectors for proper mating.
  • Verify vehicle has followed maintenance schedule.
  • Verify inertia fuel shutoff (IFS) switch is set.
  • Verify battery is fully charged (12.5 volts or greater).
  • Verify electrical/fuse integrity.
  • Verify fuel level in the tank is sufficient.

Are any concerns present?
Yes

  • REPAIR as necessary.

No

  • GO to HC2

.

HC2 CHECK VOLTAGE AT FUEL PUMP HARNESS CONNECTOR

  • Connect battery charger.
  • Verify IFS switch state. Follow the IFS switch reset procedure at the beginning of this pinpoint test.
  • Disconnect the fuel pump harness connector at the fuel pump.
  • Key on, engine off.
  • Connect a digital multimeter between the fuel pump power circuit and fuel pump ground circuit at the fuel pump harness connector (refer to the Wiring Diagrams for correct pin location).
  • Access Output Test Mode (refer to Section 2 See: Diagnostic Trouble Code Tests and Associated Procedures\SECTION 2: Diagnostic Methods ) and turn on the fuel pump circuit and monitor the voltage reading.

Was the voltage greater than 12.5 volts?
Yes

  • KEY OFF. EXIT Output Test Mode. GO to HC3

.

No

.

  • ALL others: CHECK for opens and shorts in the fuel pump power and ground circuits.

HC3 CHECK FUEL FILTER FOR PROPER MAINTENANCE

  • Locate and inspect the vehicle maintenance schedule and fuel filter. Check for last repair date.

Was the fuel filter replaced within the last 48,280 km/30,000 miles?
Yes

  • GO to HC4

.

No

.

HC4 CHECK FUEL PRESSURE

WARNING: BEFORE SERVICING OR REPLACING ANY COMPONENTS IN THE FUEL SYSTEM, REDUCE THE POSSIBILITY OF INJURY OR FIRE BY FOLLOWING DIRECTIONS IN FUEL SYSTEM CAUTION, HANDLING AND WARNING AT THE BEGINNING OF THIS PINPOINT TEST.

Note: The fuel pump will only operate for approximately 8 seconds when Output Test Mode is selected and activated.
Is the fuel pressure within the specified pressure range as stated in the Fuel Delivery System Test Information / Specification Chart?
Yes

  • GO to HC5

.

No

  • KEY OFF.For Mechanical Returnless

Fuel System with fuel pressure greater than 448 kPa (65 psi). REPLACE fuel pressure regulator in fuel tank.

  • For Mechanical Returnless

Fuel System with fuel pressure less than 310 kPa (45 psi): GO to HC6
.

  • For Electronic Returnless

Fuel Systems with fuel pressure less than 207 kPa (30 psi). GO to HC13
.

  • For Electronic Returnless

Fuel Systems with fuel pressure greater than 448 kPa (65 psi). RERUN
Quick Test. Other DTC's should be present if fuel pressure is out of
range.

  • All others:
  • Fuel pressure greater than 280 kPa (40 psi) (Cougar 415 kPa, 60 psi) onreturnable fuel systems

, GO to HC10
.

  • Fuel pressure less than 240 kPa (35 psi) (Cougar 310 kPa, 45 psi) onreturnable fuel systems

, GO to HC13
.

HC5 CHECK FUEL PRESSURE LEAKDOWN

Note: When the fuel pump is commanded off, the fuel pressure may substantially decrease and then stabilize.

Does the fuel pressure remain within 34 kPa (5 psi) of the recorded reading (RFS, MRFS) or greater than 275 kPa (40 psi) (ERFS) after 1 minute?
Yes

  • GO to HC7

.

No

  • GO to HC6

.

HC6 CHECK PRESSURE REGULATOR AND PULSE DAMPER DIAPHRAGM

  • Fuel pressure tester installed.
  • Start engine and run engine for 10 seconds.
  • Key off, wait 10 seconds.
  • Start engine and run engine for 10 seconds.
  • Key off, remove vacuum hose from fuel pressure regulator or pulse damper port.
  • Inspect for fuel in the vacuum hose or regulator port or pulse damper.

Is fuel present in the vacuum hose, regulator or pulse damper port?
Yes

  • REPLACE fuel pressure regulator.
  • For Mechanical Returnless Fuel System:
  • Replace pulse damper.

No

  • GO to HC12

.

HC7 CHECK FUEL PRESSURE, ENGINE RUNNING

  • Fuel pressure tester installed.
  • Disconnect vacuum hose at the fuel pressure regulator and plug it.
  • Drive vehicle with heavy accelerations while observing fuel pressure gauge reading.

Does fuel pressure reading hold steady within 21 kPa (3 psi) during test?
Yes

  • For Returnable Fuel Systems

GO to HC8
.

  • All Others

GO to HC12

No

  • GO to HC13

.

HC8 CHECK FUEL PRESSURE REGULATOR RESPONSE

  • Fuel pressure tester installed.
  • Install vacuum gauge to intake manifold.
  • Start engine and observe both gauges.
  • Accelerate and decelerate engine speed to vary vacuum gauge reading.

Does the fuel pressure gauge reading increase as vacuum gauge reading decreases or decrease as vacuum gauge reading increases?
Yes

No

  • GO to HC9

.

HC9 CHECK VACUUM SUPPLY

  • Fuel pressure tester installed.
  • Vacuum hose disconnected and plugged at the fuel pressure regulator.
  • Install a hand held vacuum pump to the fuel pressure regulator.
  • Start engine, remain at idle.
  • Observe fuel pressure while applying vacuum.

Does the fuel pressure change as the vacuum changes?
Yes

  • REPAIR vacuum source.

No

  • REPLACE fuel pressure regulator.

HC10 CHECK FOR RESTRICTED FUEL RETURN LINE

  • Fuel pressure tester installed.
  • Remove fuel return line at the fuel rail and connect a short hose from the fuel rail to a measure container of at least 1.1 liter (1.0 quart) capacity.
  • Key on, engine off.
  • Access Output Test Mode and run the fuel pump to obtain maximum fuel flow (one cycle of the fuel pump is all that is required).
  • Record fuel pressure and observe if fuel is being returned to the measuring container.

Is fuel pressure within specification and is fuel returning to the container?
Yes

  • KEY OFF. GO to HC11

.

No

  • KEY OFF. Fuel pressure out of specification. REPLACE fuel pressure regulator.

HC11 CHECK FUEL RETURN SYSTEM

  • Observe Warning, Caution and Handling at the beginning of this pinpoint test.
  • Disconnect fuel return line at the fuel rail.
  • Disconnect fuel return line at the fuel pump.
  • Check the fuel return line for restrictions due to blockage, kinking or pinching.
  • Apply 21 to 34 kPa (3 to 5 psi) regulated shop air to the return line pressure.

Does air flow freely through the line?
Yes

  • REPLACE the fuel pump module.

No

  • REPAIR the fuel return line.

HC12 CHECK FUEL INJECTOR FLOW AND LEAKAGE

  • Observe Warning, Caution and Handling at the beginning of this pinpoint test.
  • Check injectors for leakage and flow rate using Injector Flow Tester.

Are test results satisfactory?
Yes

  • For symptoms without DTCs and Electronic/Mechanical Returnless Fuel Systems:

RETURN to Section 3, Symptom Charts for further direction. See: Symptom Related Diagnostic Procedures

  • All others:

VERIFY no other leak exists. REPLACE fuel pump module.

No

HC13 CHECK FUEL SUPPLY LINE FOR RESTRICTION

  • Observe Warning, Cautions and Handling at the beginning of this pinpoint test.
  • Disconnect fuel supply line at the fuel rail.
  • Disconnect fuel supply line at the fuel pump.
  • Check the fuel supply line for restrictions due to blockage, kinking, or pinching.
  • Apply 21 to 34 kPa (3 to 5 psi) regulated shop air pressure to the supply line.

Does air flow freely through the line?
Yes

  • Air flows freely. REPLACE fuel pump module.

No

  • REPAIR cause of restriction.