Turn ignition switch to OFF position. Using a DVOM, measure resistance of EGRVR circuit between
PCM harness connector and EGRVR solenoid harness connector. See Fig. 244. If resistance is less than 5
ohms, reconnect EGRVR solenoid and PCM harness connectors and go to next step. If resistance is 5
ohms or more, repair open in EGRVR circuit.
86) Check EGRVR Solenoid Vacuum Output Capability By Grounding EGRVR Circuit
Disconnect hose from EGR valve. Connect vacuum gauge to EGR vacuum hose. Start engine and allow
to idle. Backprobe PCM harness connector and connect a jumper wire between EGRVR circuit at PCM
and chassis ground. See Fig. 244. If vacuum gauge reading is 4 in. Hg (13.5 kPa) or more within 2
seconds, replace PCM. If vacuum gauge reading is less than 4 in. Hg (13.5 kPa) within 2 seconds, replace
EGRVR solenoid.
90) Inspect EGR System For An Intermittent Fault
Turn ignition switch to OFF position. Visually inspect entire EGR system for deterioration or signs of
intermittent failure. Repair as necessary. If no faults are found, go to next step.
91) Inspect DPFEGR Sensor Pressure Hoses
Visually inspect both DPFEGR sensor hoses for proper connections and 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.
92) 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 next step.
NOTE:
A break in step numbering sequence occurs at this point. Procedure skips
from step 85) to step 90). No test procedures have been omitted.
2003 Ford Pickup F150
2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline