[Zagato]

Hello all. I have a 2002 Excursion 7.3, 218XXX miles. Its been mine for the last 5k miles. It is all stock and has mostly highway miles up to this point. My issue began a week ago. Monday, driving on a cool day(39 degrees), after a slight downhill while waiting at a light, it begins running as if its out of fuel, like a miss, rough idle, almost no power. It has a full tank of fuel. Limp it home. Shut it down, fires right up no issues. No codes, no smoke.

Tuesday, take it out again, about a mile from home, issue repeats. Only this time, the condition stays through a restart for a couple of tries. Finally get it to run normally and quickly get it home.
This time I get a code. I'm using FORscan.

Friday I got time to play with the truck a bit. Scanned it, get P1316. Based on the advise here, I decided to check the UVCHs. Removed both valve covers, ohmed everything out, everything to spec. Understanding that the ohm test isn't necessarily the final word, I do a buzz test and a cylinder contribution test. Everything sounded great, called it a day.

Today, tried to start, at this point it cranks well but won't start.
Rescanned the engine. P1316 went away, and I got a new code. I forgot to write it down, but the description was bad circuit to the IPR. Thinking I have not have snugged up the main harness well, I disconnected it, taped up any/all wires that looked like they had any rubbing damage and reconnected it. The code was still there, so I took a look at the IRP. I checked the end nut to make sure it didn't work itself loose, made sure the plug was still connected. Went back to the truck, cleared the codes and tried to fire it again.

Still won't start, has a stumbling turnover. The IPR code has gone and is now replaced with P0683. Checked those connections as well, still won't start.

To my question, what is my next step? The codes are wandering around the engine bay, do I begin to suspect the PCM? I do plan to drop the tank and check the in-tank filters. I did confirm the fuel pump is working. Fuel bowl is full. I have not run a fuel pressure test yet. Any advise is appreciated. Thank you.

 

[klhansen]

Try unplugging the ICP sensor wiring and see if it will start. Also check for oil inside the sensor connector. That's a sign that it's bad. When you crank it with the wiring unplugged it will throw a code for the ICP sensor and also light up the Check Engine Light, but should run OK.
[on edit] How cold is it where you are. A P0683 is a glow plug controller code. Maybe your GPCM has gone bad.

 

[Zagato]

klkhansen,

its been about 50F for the last week here. today was close to 70F. I will look into the gpcm. its just seems odd to me how the code keep moving from component to component. Thank you.

 

[greenskeeper79]

post a video of the starting and rough idle

pigtail at IPR is known to fail and need to be replaced

UVCH connections can be repaired with the 50 cent mod

 

[Zagato]

Greenskeeper, it will no longer start.

 

[greenskeeper79]

Greenskeeper, it will no longer start.

start at the basics, do you have fuel pressure at the bowl? (fuel pump and regulator working)

 

[Zagato]

At your suggestion, I started over with the basics today. Fuel pump relay is working, the pump is powering up, running for a second or two. Holding pressure at the bowl. I also doubled checked my oil levels, made sure all electrical connections are tight. As a precaution, and because the truck is somewhat new to me, I replaced the CPS with a Ford unit. No idea how old it was, so, figured I would eliminate a known weak spot.

The air filter is 1k miles new, confirmed that there is nothing obstructing the air ducting as well. Cranking strong, still no start. Its not even trying to fire. Once I get an o-ring set ordered, I will pull the lines off the fuel bowl return/regulator and give it a look. Anything else I should plan for in the way of rebuild parts while i'm ordering?

 

[Zagato]

Update, after some more reading I hooked up FORscan and did an ICP, IPR test. ICP while cranking never gets above 250-255 psi. IPR does get to 65% duty cycle. Still no start. I has added a new code, p1280, still have p0683. pulled the icp connector, still no start, no oil on connector.

 

[Davismx]

Sounds like you lost the hpop, my buddy just threw about the same situation

 

[greenskeeper79]

Update, after some more reading I hooked up FORscan and did an ICP, IPR test. ICP while cranking never gets above 250-255 psi. IPR does get to 65% duty cycle. Still no start. I has added a new code, p1280, still have p0683. pulled the icp connector, still no start, no oil on connector.

Is the HPOP full of oil? should be close to the top of the inspection port.

Could be an internal oil leak in which case you need to follow the test procedures to see if it is the pump or related components.

 

[greenskeeper79]

Fuel pump relay is working, the pump is powering up, running for a second or two.

Fuel pump should run for at least 20 seconds with the key in the on position. The low HPOP reading is the bigger issue.

 

[bigb]

Update, after some more reading I hooked up FORscan and did an ICP, IPR test. ICP while cranking never gets above 250-255 psi. IPR does get to 65% duty cycle. Still no start. I has added a new code, p1280, still have p0683. pulled the icp connector, still no start, no oil on connector.

The 65% means the duty cycle is maxed out. In other words the IPR is being commanded to open all the way to bring up the pressure but if there's an internal leak the pressure can't build enough to fire the injectors.

 

[bigb]

To answer what your next steps are like greenskeeper says you have to isolate the leak. A common failure is the injector orings. The dealership uses special fittings to dead head the pump and pinpoint the leak but there is a poor man's test that uses compressed air, Google "The Cody Test"