Ford F150 Pickup. Manual — part 1219

Gasoline Engines

1. Remove fuel cap to release fuel tank pressure. Remove relief valve service port cap. Relief valve service

port is located on fuel supply manifold. Using Fuel Pressure Gauge (T80L-9974-B), release fuel pressure
from Schrader valve.

2. If fuel pressure gauge is not available, disconnect electrical connector to Inertia Fuel Shutoff (IFS)

switch. For IFS switch location, see INERTIA FUEL SHUTOFF SWITCH LOCATIONS table. Crank
engine with IFS disconnected for 15 seconds to reduce system pressure.

FUEL PRESSURE

Bi-Fuel & Natural Gas Vehicle Engines

1) Check Fuel Pressure
Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Install Natural
Gas Fuel Rail Pressure Gauge Tool Kit (134-00114) to fuel rail Schrader valve. Using scan tool, access
FRP PID (if available) from PID/DATA MONITOR & RECORD menu. With ignition switch turned to
ON position, record FRP sensor PID or fuel pressure gauge reading. Start engine and allow to idle. Again
record FRP sensor PID or fuel pressure gauge reading. Increase engine speed to 2500 RPM and maintain
for one minute. Record FRP sensor PID or fuel pressure gauge reading. Compare measured fuel pressure
to fuel pressure specification. See FUEL PRESSURE SPECIFICATIONS table. If fuel pressure
readings are within specification, turn ignition switch to OFF position and go to next step. If fuel pressure
readings are not within specification, turn ignition switch to OFF position and go to TEST HB, step 1)
under SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG, FLEX-FUEL & GASOLINE article
for fuel delivery system diagnosis.

2) Check Fuel System For Pressure Stability

With fuel pressure gauge installed, cycle ignition switch from OFF to ON position 2 times to pressurize
fuel system (DO NOT start engine). Verify no external leaks are present. If fuel pressure does not remain
within 10 psi (69 kPa) of highest fuel pressure reading after 2 minutes, go to TEST HB, step 1) under

components.

NOTE:

For fuel pressure release procedures on Bi-Fuel and Natural Gas Vehicles
(NGV), see appropriate REMOVAL & INSTALLATION article.

WARNING:

Fuel system remains under high pressure even when engine is not
running. To avoid injury, release fuel pressure before disconnecting
any fuel system hose or component. See appropriate FUEL SYSTEM
PRESSURE RELEASE procedure under FUEL SYSTEM VENTING in
appropriate REMOVAL, OVERHAUL & INSTALLATION article.

NOTE:

Not all natural gas vehicles are equipped with Fuel Rail Pressure (FRP)
sensor. On vehicles without FRP sensor, use values supplied by fuel rail
pressure gauge.

2003 Ford Pickup F150

2003 ENGINE PERFORMANCE Basic Diagnostic Procedures - Trucks - Except Diesel

SYSTEM TESTS in SELF-DIAGNOSTICS - EEC-V - CNG, FLEX-FUEL & GASOLINE article for
fuel delivery system diagnosis. If fuel pressure remains within 10 psi (69 kPa) of highest fuel pressure
reading after 2 minutes, go to next step.

3) Check Fuel System For Pressure Stability With Ignition Switch Turned To ON Position

Using scan tool, access FRP PID (if available) from PID/DATA MONITOR & RECORD menu. If FRP
PID is not available, ensure natural gas fuel rail pressure gauge tool kit is installed onto fuel rail Schrader
valve. Cycle ignition switch from OFF to ON (DO NOT start engine). Monitor fuel pressure reading. If
fuel pressure does not remain within 10 psi (69 kPa) of highest fuel pressure reading after 10 seconds,
check for leaking fuel injectors or fuel pressure regulator. If fuel pressure remains within 10 psi (69 kPa)
of highest fuel pressure reading after 10 seconds, fuel system is mechanically okay.

Gasoline Engines

1) Fuel System Visual Inspection
Visually inspect fuel system, including fuel lines, connections, injectors and electrical connections.
Ensure Inertia Fuel Shutoff (IFS) switch is not tripped. Check condition of battery and fuses. Ensure fuel
level in tank is sufficient.

2) Check Fuel Pressure

Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Release fuel
system pressure. See FUEL SYSTEM PRESSURE RELEASE . Install fuel pressure gauge. Using scan
tool, access OUTPUT TEST MODE. For additional information, see OUTPUT TEST MODE under
ADDITIONAL SYSTEM FUNCTIONS in SELF-DIAGNOSTICS - EEC-V - CNG, FLEX-FUEL &
GASOLINE article. Command fuel pump ON and run fuel pump to obtain maximum fuel pressure.
Record fuel pressure. Compare measured fuel pressure to fuel pressure specification. See FUEL
PRESSURE SPECIFICATIONS table. If fuel pressure is within specification, go to next step. If fuel
system pressure is not within specification, go to TEST HC, step 1) under SYSTEM TESTS in SELF-
DIAGNOSTICS - EEC-V - CNG, FLEX-FUEL & GASOLINE article for fuel delivery system diagnosis.

3) Check Fuel Pressure Leakdown

With fuel pressure gauge still installed, cycle ignition switch on and off several times. Record fuel
pressure. After one minute with ignition off, fuel pressure should remain within 5 psi (34 kPa) of
maximum fuel pressure. If fuel pressure remains within specification, system is capable of maintaining
fuel pressure. If fuel pressure does not remain within specification, check for leaking fuel injectors or fuel
pressure regulator.

FUEL PRESSURE SPECIFICATIONS

(1)

WARNING:

ALWAYS relieve fuel pressure before disconnecting any fuel
injection-related component. DO NOT allow fuel to contact engine or
electrical components. See FUEL SYSTEM PRESSURE RELEASE .

Application

psi (kPa)

2003 Ford Pickup F150

2003 ENGINE PERFORMANCE Basic Diagnostic Procedures - Trucks - Except Diesel

FUEL INJECTORS

Fuel Injector Resistance

Disconnect injector harness connectors. Using digital ohmmeter, measure resistance between injector terminals.
See INDIVIDUAL INJECTOR RESISTANCE table. Replace any injector not within specification.

INDIVIDUAL INJECTOR RESISTANCE

Fuel Injector Check

Start engine and allow to idle. If engine will not start, crank engine for 10 seconds. Using a stethoscope, listen

Bi-Fuel (LPG) Engines

F150 5.4L

(2)

NGV Engines

Econoline & F250-550

80-120 (552-

827)

Gasoline Engines

Aviator

25-65 (172-

448)

Econoline & Pickup 5.4L 2V

30-55 (207-

380)

Escape, Explorer, Explorer Sport, Explorer Sport Trac, Mountaineer & Ranger
(Except 3.0L Flex-Fuel)

50-65 (345-

448)

Expedition

35-65 (240-

448)

Ranger 3.0L Flex-Fuel

40-50 (275-

380)

All Others

30-45 (207-

310)

(1)

Check pressure with key on and engine off and fuel pump running.

(2)

Information is not available from manufacturer.

Engine

Ohms

Aviator, Blackwood, Econoline 4.6L & 5.4L (Except NGV), Escape 2.0L, Expedition & Pickup
4.6L & 5.4L (Except NGV), Excursion, Expedition & Navigator

13.8-

15.2

Econoline & Pickup 5.4L (NGV)

4-6

Escape 3.0L

13.1-

14.5

Econoline, Pickup & Excursion 6.8L, & Explorer, Explorer Sport, Explorer Sport Trac,
Mountaineer & Ranger 4.0L SOHC

11-18

All Others

11.4-

12.6

2003 Ford Pickup F150

2003 ENGINE PERFORMANCE Basic Diagnostic Procedures - Trucks - Except Diesel

for clicking sound at each injector. If clicking sound is heard, fuel injector is operating. If clicking sound is not
heard, see TEST HD: MISFIRE DETECTION MONITOR under SYSTEM TESTS in SELF-
DIAGNOSTICS - EEC-V - CNG, FLEX-FUEL & GASOLINE 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 inertia switch is manually reset. To reset inertia switch, depress button on

switch. See INERTIA FUEL SHUTOFF SWITCH LOCATIONS table.

INERTIA FUEL SHUTOFF SWITCH LOCATIONS

IGNITION CHECKS

PRELIMINARY CHECKS

Before diagnosing problems in ignition system, ensure following systems and components are in good condition
and operating properly:

z

Battery.

z

Timing belt or chain.

z

Fuel delivery and injection system.

z

All wiring and vacuum connections.

z

Air cleaner and ducts.

z

Cooling system.

EDIS (DISTRIBUTORLESS) IGNITION SYSTEM

WARNING:

DO NOT reset Inertia Fuel Shutoff (IFS) switch until fuel system has been
inspected for leaks.

Application

Location

RV Cutaway

On Lower Right Of Steering Column

Windstar

On Right Rear Side Of Vehicle

All Others

Behind Right Kick Panel

NOTE:

If vehicle is a no-start, see NO-START/NORMAL CRANK under SYMPTOMS in
TROUBLE SHOOTING - NO CODES - EEC-V - CNG, FLEX-FUEL & GASOLINE
article, or TEST A: NO-START under SYSTEM TESTS in SELF-DIAGNOSTICS -
EEC-V - CNG, FLEX-FUEL & GASOLINE article.

NOTE:

Aviator, Blackwood, Econoline & Pickup 4.6L, 5.4L and 6.8L, Escape 3.0L,
Expedition 4.6L and 5.4L, Excursion 5.4L and 6.8L, Explorer and Mountaineer

2003 Ford Pickup F150

2003 ENGINE PERFORMANCE Basic Diagnostic Procedures - Trucks - Except Diesel