6.4 Powerstroke Fuel Pressure issues Help!

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I'm stilling having issues with my truck and I don't know what to do. Originally my truck was losing fuel pressure after sitting for a while; for example I would get in my truck in the morning start it up pull out of the driveway and the rail pressure would drop down, I'd lose power, and the truck would run ruff but the truck never stalled and if I let off the throttle and got back into it the truck would run fine.

So after doing this I pulled the fuel filters (on my Airdog) and cut them open with a filter cutter to find metal in the filters. So I had the fuel system replaced and cleaned, and the truck still does the exact same thing but now it does it every time I turn my truck off. After this I had the Airdog replaced and had the rail pressure sensor replaced, and the same thing is still happening.

The only code I'm getting is related to the low rail pressure, I have 10psi coming from my Airdog, and the truck runs just fine after I get over the first hiccup. Also I'm running a mini maxx with ******** tunes.

Can somebody help me I don't know what to do?
 

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Are you watching rail pressure commanded and desired when it happens? What does lift pump pressure do when it happens[/QUOTE

Yea, the PCM is commanding correctly but the pressure is still dropping off. It acts like the PCM is loosing communication with the rail pressure sensor, would that be a PCM issue then?
 

sootie

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If it turns out you need a pcm, i think i may have one laying around...
 

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So my truck is at the dealer now, and it has 2 hard codes; the first one is P0102 Mass air flow sensor. The dealership traced the wires and replaced the sensor and the code is still there. The second code is p2291 which is for low injection pressure; once the truck warmed up they checked the actual verse command rail pressure form 5000 to 20000, they said it takes about 20-30 seconds for the actual to reach the commanded. They are thinking the PCM is bad, but wanted me to check with gear head to make sure these codes where not common when using their tunes on a mini maxx. I'm sure they are not common but I'm going to double check with gear head and then have them replace the PCM.

The dealership also told me they needed two keys to swap the PCM and I only own one key for my truck, is this true? And will they have any issue reprograming a used PCM to my truck?
 

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Dealership put my used PCM in the truck today, the mafs code went away but the PCM doesn't recognize my keys so they can't start it, they are telling me the only way to get the keys to read properly is to get a new PCM from ford. I think this is incorrect, can anybody tell me how to get the new PCM to read the keys?
 

sootie

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Dealership put my used PCM in the truck today, the mafs code went away but the PCM doesn't recognize my keys so they can't start it, they are telling me the only way to get the keys to read properly is to get a new PCM from ford. I think this is incorrect, can anybody tell me how to get the new PCM to read the keys?

thats bs. they need to flash your used pcm with the correct vin of the truck and reset the pats system
 

sootie

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Thank you! I'm going to let him know tomorrow.
Basically they need to enter the trucks vin on the pcm and flash it as if they were doing a regular update. Try the keys. If that still doesn't work, reset the pats
 

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Basically they need to enter the trucks vin on the pcm and flash it as if they were doing a regular update. Try the keys. If that still doesn't work, reset the pats

They already put my vin in the PCM and the keys wouldn't work, I'll let him know about the Pats, hopefully that will take care of it.
 

sootie

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They already put my vin in the PCM and the keys wouldn't work, I'll let him know about the Pats, hopefully that will take care of it.

you could also program the keys yourself with forscan if it came to that.
 

6.0 Tech

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A pats parameter reset should fix it. You dont even need both keys to do that. It even says in ids that you need to perform that step in order for it to work right. You may wanna try a different dealer if they cant read....
 

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I just talked to the dealer he said he enter my vin into the PCM and put fords as build data into my PCM. He said he reset the PATS and the keys still didn't work, he's going to try again. He also told me he never has these issue on 6.0 or 6.7 just 6.4, is there something he is missing or something he is doing incorrectly?
 

sootie

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I just talked to the dealer he said he enter my vin into the PCM and put fords as build data into my PCM. He said he reset the PATS and the keys still didn't work, he's going to try again. He also told me he never has these issue on 6.0 or 6.7 just 6.4, is there something he is missing or something he is doing incorrectly?

is the red padlock on the dash blinking? Could always try turning the ignition on and then using the jumper wire beside the passenger battery. Sometimes if it starts that way, it will reset the pats itself.
 

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is the red padlock on the dash blinking? Could always try turning the ignition on and then using the jumper wire beside the passenger battery. Sometimes if it starts that way, it will reset the pats itself.
I have had that happen to me twice. No rhyme or reason got in tried starting the truck saw the blinking light got out used the jumper wire and it fired right up. I seemed to only happen when I was running 1 battery. Now that I have two back in the truck it has not happened in over a year.
 

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