I have a 99' F350 Duely with a 7.3L Diesel and single turbo. It also has 213k miles. It has just started running very rough, almost like missing. It does this at idle and at slower speeds after it is warm. I have replaced the fuel filter and run injector cleaner through it. So far, no change. At times, it is very hard to start and will run the batteries down trying to get it started. I love my pickup but have little to no experience with diesel engines.


The only code is P0475 for exhaust back pressure. I talked to my local Fort Tech and he stated that it would not cause it to run rough unless the butterfly was stuck closed.


I do have a programmer and had the pickup set for performance. I set it back to factory to see if that would change anything and it didn't. I am lost since there is not a code to explain what it going on.


Any and all help would be greatly appreciated.

 

This process will get you started.

echo=on
HARD START/NO START DIAGNOSTICS

**NOTE: A hard start/ No start concern with EOT Temp. Below 60F perform step 10 first.


Tools: Fuel Filter Cap Removal Tool / Flash Light / Tools Flash Light /

White Bond Paper / Stop or Wrist Watch w/Secong Hand Sweep / DVOM

Step #1: Visual Engine/Chassis Inspection

Tools: Flash Light

Fuel Oil Coolant Electrical Hoses Leaks Check

Tools: White Bond Paper

Step #2 Check for contaminates Correct Grade and Viscosity Miles/Hours on oil, correct level.

Step #3 Intake/Exhaust Restriction

Tools Flash Light

Inspect air filter and ducts -exhaust system / Inspect exhaust back pressure device

Step #4 Sufficient Clean Fuel

Tools: Fuel Filter Cap Removal Tool

a. Check if the WATER IN FUEL lamp has been illuminated.
b. After verifying that there is fuel in the tank, drain a sample from fuel filter housing at
key on.
c. NOTE: Fuel pump will run for 20 sec. at key on

Step #5 Electric Fuel Pump Pressure

Tools: DVOM / Fuel Port Adaptor and Pressure Gauge 0-160 PSIG

a. Verify that the fuel pump has voltage and gnd. present at key on.
b. Measure fuel pressure at the Fuel Bowl Test Port key on.
c. Instrument Spec. 45 PSIG min. / WOT Under Load =/> 42 PSIG.
* If pressure fails low, go to step 8c on the Performance side of this sheet to identify cause

Step #6 Perform KOEO On Demand Test

Tools: OBD-II On-Board Diagnostics, Phase 2 Vehicle Media Communications Unit (Scanner)
DTCs set during this test are current faults.
Note: IDM DTCs displayed here could be current or historical faults

Step #7 Retrieve Continuous Trouble Codes

Tools: OBD-II On-Board Diagnostics, Phase 2 Vehicle Media Communications Unit (Scanner)

DTCs retrieved during this test are historical faults. Note: IDM DTCs are cleared when codes are cleared.

Step #8 KOEO Injector Electrical Self-Test

Tools: Bi-Directional Scan Tool.

a. All injectors will momentarily buzz, then individual injectors will buzz in sequence 1 through 8. IDM DTCs may be transmitted after test is completed.
b. Note: IDM DTCs may be historical if not cleared above.

Step #9 Data List Monitoring

Tools: OBD-II On-Board Diagnostics, Phase 2 Vehicle Media Communications Unit (Scanner)

1. Select the parameters indicated from the NGS parameter list and monitor while cranking engine.

Parameter/Spec:
a. V PWR / 10.5 volt min.
b. RPM / 100-150 RPM minimum
c. ICP / 500 PSI or 3.4mPa min.
d. ICPv / 0.25v – 0.30v
e. FUEL PW / 1 mS to 6mS
* V PWR -If indicating a low voltage condition, check battery voltage, charging system or power and ground circuits to the PCM. GO TO PINPOINT TEST A

* RPM -Low RPM could be an indication of starting/ charging system problems,

RPM indicated with the engine cranking -could be CMP circuit fault, check for Diagnostic Trouble Codes. GO TO PINPOINT TEST DG

*ICP -A minimum of 500 PSI (3.4 mPa) is required before the injectors are enabled. No or low oil in the reservoir, system leakage, injector O-Rings or faulty IPR could cause pressure loss.

*Go to section 4 step 9c in the PC/ED Manual for a detailed description on how to perform this test. Note: If no RPM signal is received, IPR duty cycle will default to 14%

*FUEL PW -Even though a 1 to 6 mS FUEL PW is shown, it’s possible the IDM did not receive the signal due to a CI or FDCS circuit fault or internal IDM failure.

Step #10 Glow Plug System Operation

Tools: DVOM / Stop or Wrist Watch w/Secong Hand Sweep

a. Glow Plug ON time is dependent on oil temperature and altitude. The Glow Plug relay comes on between 1 and 120 sec. and does not come on at all if oil temp is above 131 F.
b. Verify that B+ is being supplied on the large BK/W wire going to the Glow Plug relay.
c. Install a voltmeter to the glow plug feed terminal (two brown wires or center terminal on the shunt).
d. Using a Bi-Directional Scan Tool and EOT PID’s, verify glow plug "on" time.
e. Turn key to run position, measure voltage ("on “time) (Dependent on oil temperature and altitude) Relay on time Spec. Measurement 1 to 120 seconds B +
f. Note: Wait to Start Lamp "on" time (1 -10 sec.) is independent from Glow Plug "on" time
g. Glow Plug Resistance
h. Remove both 9 pin connectors from valve covers • Measure each Glow Plug resistance to Bat. Ground. Measure engine harness resistance to relay. .1 to 2 ohms
i. Glow Plug Connector to relay 0 to 1 ohms
FRONT
#2 #1
#4 #3
#6 #5
#8 #7

*Add 5 seconds to glow plug on time when above 7000 feet in altitude, but not to exceed 120 seconds.
echo=off

 

Thank you Tom for your help. After further checking, it turned out to be the Cam Position Sensor. I was happy that it was about a $12 fix and took me about 5 minutes to change it out.

 

Glad you got it fixed and thank you for letting us know what the fix was.

You say $12 fix. Did you buy a Ford part or an auto parts store part. If it was the auto parts store I recommend you get a Ford part and keep it in the glove box with a 10mm wrench. These trucks really do not like aftermarket sensors and you can find lots of threads were weird running issues or shut downs are cured by replacing with Ford or Motorcraft.

 

As its been stated a gazillion times, DO NOT use store sensors. With that price, its definitely not a Motorcraft. Get one from a dealer and get a spare as well. With those mils too, I would spend a little time learning the truck or it's going to cost you big if you have to take to the dealer or a "mechanic" to misdiagnose and charge you lots of $$.