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Discussion Starter · #1 ·
Ok, It was -10 a few weeks ago here in beautiful north central Illinois and My truck just died. Had it plugged in all night, started really hard like 2 minutes to get it cranked over, let it warm up for about 5 min (was running late), got about a mile down the road and it just died. No spitting and spuddering just flat lined. A few days later I changed the fuel filter (figured it gelled up) and Still nothing. No signs that it is getting any fuel. I was running stanadine Lubricity formula but no anti-gel. Primed and cracked the bleeder screw on the filter housing and it would start and run nice and smooth while my friend was pumping the primer but it would die a few seconds after the primer was not being pumped. Pumped the primer bulb like 100 times and it doesn't get very hard, Never really did since I bought it a few months back. Got a filter housing rebuild kit and tried it again, same results. Took off the return line and when I pump the primer about 1/2 cup of fuel came out of the return line with only 15 pumps. Could this be a Fuel Pressure Relief Valve or a Fuel pressure Regulator? Thanks in advance! :help:help:help
 

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Ok, It was -10 a few weeks ago here in beautiful north central Illinois and My truck just died. Had it plugged in all night, started really hard like 2 minutes to get it cranked over, let it warm up for about 5 min (was running late), got about a mile down the road and it just died. No spitting and spuddering just flat lined. A few days later I changed the fuel filter (figured it gelled up) and Still nothing. No signs that it is getting any fuel. I was running stanadine Lubricity formula but no anti-gel. Primed and cracked the bleeder screw on the filter housing and it would start and run nice and smooth while my friend was pumping the primer but it would die a few seconds after the primer was not being pumped. Pumped the primer bulb like 100 times and it doesn't get very hard, Never really did since I bought it a few months back. Got a filter housing rebuild kit and tried it again, same results. Took off the return line and when I pump the primer about 1/2 cup of fuel came out of the return line with only 15 pumps. Could this be a Fuel Pressure Relief Valve or a Fuel pressure Regulator? Thanks in advance! :help:help:help
Just for clarity what return line did you remove?
 

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Discussion Starter · #3 ·
The return going to the fuel tank.
 

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mine did the same thing when my CP3 let go. wasnt sucking any fuel to the pump
 

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My first though was the CP3 also if there is no air in the system. I may also be injectors returning too much fuel but the truck usually will continue running when started. So, first disconnect the outgoing fuel line from the filter and put a hose on it into a bucket. Then pump the primer to make sure there isn't a fuel line clogged causing the issues. If there is good fuel flow your issue is likely a bad CP3.

If you want to test the return of the CP3 remove the return line and measure the fuel after cranking for 15 seconds. If it exceeds 35ml/15 seconds of cranking then it's bad and returning too much fuel. If it's within spec check the injectors.

Remove the main return form the drivers side or passenger side and measure the fuel returning to the tank from each side separately. Spec is 3ml per injector for 15seconds cranking. Or 12ml per bank for 15 seconds cranking.
 
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