Ford F150 Pickup. Instruction — part 1512

performed to verify repair. If downstream hose connections are okay, go to next step.

61) Inspect Downstream Pressure Hose For Plugging
Check downstream hose for proper routing. Ensure downstream hose is not pinched and that hose routing
does not have low spots where water may collect, freeze and plug hose in colder climates. Repair or
replace hose as necessary. Perform DRIVE CYCLES. Ensure EGR MONITOR PROCEDURE is
performed to verify repair. If downstream hose is okay, go to next step.

62) Check Orifice Tube Assembly & DPFEGR Sensor

Inspect DPFEGR sensor downstream connection for plugging or damage. See Fig. 245. Inspect intake
manifold side pressure pick-up tube and orifice tube assembly for plugging, loose connection or damage.
Repair or replace DPFEGR sensor or orifice tube as necessary. Perform DRIVE CYCLES. Ensure EGR
MONITOR PROCEDURE is performed to verify repair. If no faults are found, go to next step.

63) Check DPFEGR Sensor Output By Applying Vacuum With Hand Pump

Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Disconnect
pressure hoses at DPFEGR sensor. Connect hand vacuum pump to downstream connection at DPFEGR
sensor (intake manifold side or smaller diameter port). See Fig. 239. Using scan tool, access DPFEGR
PID from PID/DATA MONITOR & RECORD menu. Read the following DPFEGR PID values with
ignition switch in ON position:

z

DO NOT apply vacuum to sensor. Record DPFEGR PID value. DPFEGR PID value should be .2-
1.3 volts.

z

Using vacuum pump, apply 8-9 in. Hg (27-30 kPa) for 5 seconds. DPFEGR PID value should
increase to more than 4 volts.

z

Quickly release vacuum. DPFEGR PID value should drop to less than 1.5 volts within 3 seconds of
releasing vacuum.

If any DPFEGR PID values are not as specified, replace DPFEGR sensor. If all DPFEGR PID values are
as specified, reconnect DPFEGR sensor. Unable to duplicate or identify fault at this time, go to TEST Z,
step 1).

70) For Continuous Memory Only DTC P0401: Perform KOER Self-Test
DTC P0401 indicates EGR MONITOR failed due to PCM detecting EGR flow is less than desired
minimum while driving. Possible causes for this fault are:

z

Vacuum Supply

NOTE:

Ensure DPFEGR pressure hose is the correct repair part and not a
substitute.

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips
from step 63) to step 70). No test procedures have been omitted.

NOTE:

For additional testing information, see DIAGNOSTIC AIDS.

2003 Ford Pickup F150

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline

z

EGR Valve Stuck Closed

z

EGR Valve Leaks Vacuum

z

EGR Flow Path Restricted

z

EGRVR Circuit Shorted To PWR

z

VREF Circuit Open To DPFEGR Sensor

z

DPFEGR Sensor Downstream Or Upstream Hoses Disconnected, Reversed Or Restricted

z

VPWR Circuit Open To EGRVR Solenoid

z

Damaged EGR Orifice Tube

z

Faulty EGRVR Solenoid

z

Faulty PCM

If fault is currently present, KOER DTC P1408 should be present. Perform KOER ON-DEMAND
SELF-TEST. If DTC P1408 is present, go to next step. If DTC P1408 is not present, go to step 90).

71) For KOER Only DTC P1408: Retrieve Continuous Memory DTCs
DTC P1408 indicates KOER self-test failed due to measured EGR flow falling below or exceeding
required calibration. Possible causes are:

z

Vacuum Supply

z

EGR Valve Stuck Closed

z

EGR Valve Leaks Vacuum

z

EGR Flow Path Restricted

z

EGRVR Circuit Shorted To PWR

z

VREF Circuit Open To DPFEGR Sensor

z

DPFEGR Sensor Downstream Or Upstream Hoses Disconnected, Reversed Or Restricted

z

VPWR Circuit Open To EGRVR Solenoid

z

Damaged EGR Orifice Tube

z

Faulty EGRVR Solenoid

z

Faulty PCM

Retrieve all Continuous Memory DTCs. If DTC P1406 is present, go to step 60). If DTC P1406 is not
present, go to next step.

72) Perform KOER Self-Test While Monitoring EGR Vacuum

Disconnect vacuum hose from EGR valve and connect hose to vacuum gauge. Since EGR vacuum hose is
disconnected, disregard any DTCs during this KOER self-test. Perform KOER ON-DEMAND SELF-

NOTE:

For additional testing information, see DIAGNOSTIC AIDS.

NOTE:

If any DTC other than DTC P1406 is present, service those DTCs after
completing this test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS.

2003 Ford Pickup F150

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline

TEST while monitoring gauge. About 30 seconds into KOER self-test, EGR flow will be requested for a
few seconds. Vacuum reading on vacuum gauge should increase to more than 1.6 in. Hg. If vacuum
reading increases to 3.0 in. Hg or more, vacuum is sufficient to open EGR valve. Fault is likely to be in
EGR vacuum control system. Turn ignition switch to OFF position and go to next step. If vacuum reading
stays less than 3 in. Hg, vacuum is insufficient to open EGR valve. Turn ignition switch to OFF position
and go to step 80).

73) Inspect DPFEGR Sensor Pressure Hoses

Check both DPFEGR sensor hoses for correct routing. See Fig. 245. Ensure downstream and upstream
hoses are not pinched and that hose routing does not have low spots where water may collect, freeze and
plug hose in colder climates. Inspect DPFE sensor and orifice tube assembly for restriction or damage at
pick-up tubes (ports). Repair as necessary. If no faults are found, go to next step.

74) Check DPFEGR Sensor Output By Applying Vacuum With Hand Pump

Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Disconnect
pressure hoses at DPFEGR sensor. Connect hand vacuum pump to downstream connection at DPFEGR
sensor (intake manifold side or smaller diameter port). See Fig. 239. Using scan tool, access DPFEGR
PID from PID/DATA MONITOR & RECORD menu. Read the following DPFEGR PID values with
ignition switch in ON position:

z

DO NOT apply vacuum to sensor. Record DPFEGR PID value. DPFEGR PID value should be .2-
1.3 volts.

z

Using vacuum pump, apply 8-9 in. Hg (27-30 kPa) for a few seconds. DPFEGR PID value should
increase to more than 4 volts.

z

Quickly release vacuum. DPFEGR PID value should drop to less than 1.5 volts within 3 seconds of
releasing vacuum.

If any DPFEGR PID values are not as specified, replace DPFEGR sensor. If all DPFEGR PID values are
as specified, reconnect DPFEGR sensor and go to step 76).

76) Check EGR Valve Function By Applying Vacuum With Hand Pump

Turn ignition switch to OFF position. Disconnect and plug vacuum hose at EGR valve. Ensure a hand
vacuum pump is connected to EGR valve. Start engine and allow to idle. Using scan tool, access
DPFEGR and RPM PIDs from PID/DATA MONITOR & RECORD menu. Slowly apply 8-10 in. Hg
(27-34 kPa) to EGR valve and hold for 10 seconds. It may be necessary to increase engine speed to obtain
1000 RPM. DPFEGR PID values should read as follows:

z

EGR valve should start opening at about 1.6 in Hg (5.4 kPa) vacuum as indicated by increasing
DPFEGR PID value.

z

As vacuum increases, DPFEGR PID voltage reading should increase. DPFEGR PID must read 2.5
volts or more with full vacuum applied.

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips
from step 74) to step 76). No test procedures have been omitted.

2003 Ford Pickup F150

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline

z

As DPFEGR voltage reading increases, EGR valve should open fully. When vacuum is held steady,
DPFEGR PID voltage reading should also hold steady. If voltage drops within a few seconds, EGR
valve or vacuum source may be leaking.

If DPFEGR PID voltage reading operates as specified, reconnect all components and go to step 82). If
DPFEGR PID voltage reading does not operate as specified, remove EGR valve and check for
contamination, wear, carbon deposits, binding, leaking diaphragm or other damage. If EGR valve is okay,
check for obstructed EGR port in intake manifold or restricted orifice tube assembly. Repair as necessary.

80) Check Vacuum Source & Vacuum Hoses To & From EGRVR Solenoid

Inspect vacuum hoses between EGRVR solenoid and EGR valve for leaks, restrictions, damage or
incorrect routing. Repair as necessary. If hoses are okay, go to next step.

81) Check Engine Vacuum

Disconnect EVR vacuum hose at vacuum source. Connect vacuum gauge to vacuum source. Start engine.
With engine warm and at idle, monitor vacuum gauge. If the vacuum gauge is steadily reading a
minimum of 15 in. Hg (51 kPa), go to next step. If the vacuum gauge is not steadily reading a minimum
of 15 in. Hg (51 kPa), isolate possible base engine concern and repair as necessary.

82) Check VPWR Voltage To EGRVR Solenoid

Turn ignition switch to OFF position. Disconnect EGRVR solenoid. Turn ignition switch to ON position.
Using a DVOM, measure voltage between negative battery terminal and VPWR circuit at EGRVR
solenoid harness connector. See Fig. 244. If voltage is more than 10.5 volts, go to next step. If voltage is
10.5 volts or less, repair open in VPWR circuit.

83) Measure EGRVR Solenoid Resistance

Turn ignition switch to OFF position. Using a DVOM, measure resistance between EGRVR solenoid
connector terminals. If EGRVR solenoid resistance is 26-40 ohms, go to next step. If EGRVR solenoid
resistance is not 26-40 ohms, replace EGRVR solenoid.

84) Check EGRVR Circuit For Short To PWR In Harness

Ensure ignition switch is in OFF position. Disconnect PCM connector(s). Inspect connector for loose,
damaged or corroded terminals. Repair as necessary. Turn ignition switch to ON position. Using a
DVOM, measure voltage between negative battery terminal and EGRVR circuit at PCM harness
connector. See Fig. 244. If voltage is one volt or less, go to next step. If voltage is more than one volt,
repair short to PWR in EGRVR circuit.

85) Check EGRVR Circuit For Open In Harness

NOTE:

A break in step numbering sequence occurs at this point. Procedure skips
from step 76) to step 80). No test procedures have been omitted.

2003 Ford Pickup F150

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline