Have a 2006 6.0 while driving after it gets hot it will just shut down as if the key was turned off. After it turns off it will not restart, if I wait about 20 min it will restart and run again until it gets hot and then shut off again. I have a scanner and while driving I am monitoring the IPR and all looks good. When it shuts down the IPR will show about 600 at cranking. FICM voltage is at 52 as I have done the upgrade. FICM vehicle voltage is at 13volts. Have not checked fuel pressure at this point but the question I have is will a bad fuel pump just shut down the truck or would I have symptoms like I was running out of fuel first? Any advice would be great thank you.


Here are the readings when truck died and trying to crank.


IPR went from 25% to 15%
ICP volts went from .50 volts to .96 volts
ICP Actual went from 585 to 200 then to 0
ICP desired went from 585 to 610

When I tried to restart at that time
desired was 600
actual was at 1300

volts was at 1.85
IPR percent was at 75%


If it was an oil leak would the ICP be at 1300 would it not be at closer to 0. If I understand this right the IPR is at 75% which is why the ICP is at 1300 psi. But that seems to me that the HPOP is working as it should and the problem is not in the HPOP system. the FICM looks good as well


car voltage is at 13.00
ficm is at 52 volts as I have done the upgrade when I had it repaired.


does not drop off when it dies and is all with in specs when I am trying to restart.


Any Ideas would help

 

I just checked the ficm sync when running it is yes and also checked the cmp to ck sync and it is toggling. is this normal? I am waiting to see what happens when it dies. Could the crank or cam sensor be going bad causing the stall and no start till it cools off?

 

I'm leaning towards an IPR. That's where I would start. Generally if the cam sensor/harness goes bad it won't restart intill you wiggle the harness next to the fuel filter housing.

 

Ok after some looking today i have found that the truck dies and just before this happens the ficm sync drops. While trying to restart i dont get a sync. The cam and crank sync while running toggles from sync to no sync. This is the same when it dies just takes longer for it to sync while cranking. After it has died i did wiggle the harness around the ficm and oil filter and was able to get it to refire. Should the cam and carnk sync be toggling or should it always be in sync?

 

Well, with your ICP pressure at 1300. When hot. Throw a cam sensor in it. Weird that you don't have a code for the cam sensor..... If your ICP pressure is that high when cranking and it won't start, the cam sensor should be your problem. I usually also repair the harness going to the sensor. As that's generally the issue. Let me know if that helps.

 

Should the cmp and ckp sync toggle. When it is running it does. Just before it dies I loose FICM Sync. When I try to start again the cmp and ckp sync toggles and there is no FICM Sync. If I move the wires next to the fuel filter it will fire up again. I am going to start to look for a bad wire and chaffing. Any idea what the color if the wire is that goes to the ficm from the pcm for the sync signal?

 

There are two wires, they clip onto one of the metal fuel lines. At that junction is where the issue is. I remove the harness cover at that section where those two wires come out and go down the front of the left side of the engine. I 9 times out of 10 install a new pigtail and extend the wires to top of the harness bundle. Where we uncovered the two wires, next to the fuel filter housing. Tape up the freshly made harness section, fish it down the front of the engine and plug it in. Done. Although I will say that I have had to replace the entire harness for just that reason also. Generally my customers need there truck ASAP, and digging for a short is labor intensive to say the least! But if that does not fix it, next step would be pull the harness and replace the entire length of the cam sensor wires, To the PCM.

 

OK here is the latest, repced the cam sensor as I could not find any problems with the wiring. ran for a little longer so I though that it was now good. Went to the store died on the way home only about 7 miles. restarted after a couple o mi and tn amost made it ba hme died again. Got pulled hme and started up again put the scanner on it no codes and looked at live streaming. Just as the car died lost ficm sync and the IPR jumped from 25% to 45 % ICP was at about 590 and dropped off just after FICM sync was lost. When trying to restart no FICM Sync ICP is showing 780. Not sure where to go from here. also the cmp and ckp sync toggles. Any help would be appricaited.


Could the wires for the sync be broken in coating and not be chaffed? and as the wires get hot casing them to drop the sync?
another thing that seems not right is the scanner is reading battery olts at 12.5 but when I put the volt meter on the batteries it shows 13V may be having an alternator problem could this be the reasn it is stalling don't see a drop in battery voltage before it stalls.

 

6.0 truck dies after you put it in gear or when you come to a stop I notice it only does this when the engine is hot when it’s cold it drives fine I see a guy had the 2006 6.0 with the same issue on here did he figure out what it was, my truck is doing the same thing.

 

You need a scan tool that also reads codes thoroughly. I recommend ForScan and an OBDII adapter that is paired to the smartphone you have (ie i-phone r android).

The phone download is $6 and the adapter (I like BAFX brand for there low cost AND they work) - $35 (ish).

Scan for codes and post them.

Most likely you have a leak, a weak HPOP, or a bad IPR valve.

One thing you have to remember is that the IPR %Duty Cycle is a commanded value, not an actual valve position. If the valve is stuck, you can have a command to be fully closed but in reality it might be FAR from fully closed.