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7.3 L Diesel

My 7.3 L 2000 4WD Excursion is experiencing power loss on hills. I have been thoughtful diagnostically and attempted to do homework to understand what seems narrowed down to a fuel issue. Granted, in my zeal for cheaper fuel, I likely dug my own pit by using wvo improperly. The following is an outline form of what I have attempted thus far to get a fix on this. Any one’s thoughts are welcome.



Potential Causes:

1. Using improperly heated and filtered veg oil

2. Corrected this by running multiple tanks of diesel and kerosene through the tank

3. There had been an ?Edge performance product? inserted in the OBD 2 sensor port when I purchased the vehicle second hand. The dash board element is removed but I am not certain if there is another location for another chip.


1. Experiencing power loss up hills

a. Bogging down when asked to accelerate.

2. Auditory perception of ?water in fuel?

3. Tactile feeling of ?shuddering? experienced by all in the vehicle.

4. No check engine light turns on.

5. The overhead factory installed mileage indicator display malfunctions intermittently (red herring?)

Attempts at diagnosis:


1. 1211

2. 1280

3. A cam speed sensor showed up at one point also.

4. 0678, 0671, 0672, 0674- - glow plug codes. glow plugs all changed on driver?s bank and still intermittently showing up.

5. My mini scanner does not have the first two codes and they did not show up at the mechanic when I spent my grand.


1. Fuel Filter replaced (several times)

2. Number four injector replaced.

3. Used kerosene.

4. Used sea foam injector cleaner

5. Replaced head gasket with integral wire harness.

6. Replaced conical K&N filter element.

7. When experiencing the ?balking, missing, ?wet fuel? sounding power loss?,? will let off on speed which ameliorates the condition

8. Stopping and ?letting her cool off for five minutes.?

9. Have replaced two PCM?s this year. This due to the engine ?quitting? while driving.

Thoughts by Mechanics: ICP ? Injection Control Pressure malady.

1. Failed or Sticking IPR (Injection Pressure Regulator)

2. Failed or Weak HPOP (High Pressure Oil Pump)

3. Low Fuel Pressure (Rare)

4. Shorts between the IPR wires or between IPR wire and ground.

Running improperly refined bio-diesel can cause problems with the seals in the injector pump and injectors.

Vegetable oil contains amino acid. And if this isn’t removed from the bio-diesel during the refining process, these acids can attack the seals in the fuel system. The seals in any fuel system are never designed to be exposed to any kind of acid.


As tester stated WVO has Free Fatty Acids and water entrained. If the WVO was converted to biodiesel, the methanol, base catalyst, soap, water, and glycol have to be separated meticulously. The final filtration has to be to a micron level below the filtration fineness of the engine filters.

Hopefully, you did not use unconverted, untreated WVO. The FFA and water would cause all sorts of problems of corrosion and gumming that any fuel system cleaner would not touch.

When #4 injector was removed, was an disassembly and fault analysis done? I am wondering if there is a final fuel filter in the feed to the injector. Correct me if I am wrong but I believe that these are unit injectors with the fuel metering solenoid and the high pressure injection solenoid on the unit.

Maybe we all can gain information from your experience, so post back any progress or further information on this situation.