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Discussion Starter #1
It cranks but rail pressure reads .3 on my Edge. Fuel filter was replaced and Seafoam was put in the filter housing. I can hear the lift pump when I bump the key. What would make the RP be so low?

Truck was running but had bad blowby and rear main was leaking before I tore it down. Broke rings on 1 and 4.
 

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Have you checked how much fuel your lift pump is putting out and how much your CP3 is putting out?
 

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Discussion Starter #4
I have not checked the output yet. I'm going through and double checking all my connections are tight first. I forgot my ground strap at the back of the head. The only codes I had at first were the fan and TCC Solenoid. I disconnected the FCA after I didn't get RP, to no avail, and now I get a P0251. I think that was from disconnecting the FCA though. Gonna double check my valve lash too. One guy said that if they are set correctly, it won't get RP. Not sure about that one but it's worth a try to check them.
 

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Yeah good idea double check all grounds on engine/ECM and TIPM
Valves adjust should be checked but usually have nothing to do with RP.
Should check lift pump supply, could check fill fuel filter in 10-15 seconds be prepared to catch overflow.
Fan in rare cases could short ECM so disconnect see if RP goes away.
 

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Discussion Starter #6
I checked the lift pump and it flows pretty good. Then I moved to the CP3. I pulled the line from the bottom of the fuel rail and put it in a bucket, cranked it over for about 10 seconds and it dribbled out of the hose (that is the supply, right?). Could it have air in the lines?
 

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Discussion Starter #8
What would cause an injector to return too much fuel? These injectors worked fine before and they sat in a bag until I installed them. Can I clean them some kind of way? I am ordering me a fuel line cap to see what happens next. I'm just ready for this thing to run again.
 

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Bad injector can cause it to have a high return rate. These injectors have very tight tolerances, so even a really small piece of debris can cause an issue. The only way we can clean them is to run a cleaner through the fuel system.
 

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How long did you crank? Sometimes it will take 30 seconds of straight cranking to prime the system.

Its not gonna start on seafoam alone. LOL Hopefully you didn't load the whole housing full.
 

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New connector tubes? I would check torque on them.
 

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Discussion Starter #12
How long did you crank? Sometimes it will take 30 seconds of straight cranking to prime the system.

Its not gonna start on seafoam alone. LOL Hopefully you didn't load the whole housing full.
Um, OK it was less than 30 seconds. Probably not more than 10 seconds at a time. And of course I didn't fill it with seafoam :wink2:, it was probably 75% full of seafoam. Ok, so drain the seafoam for later, check:

New connector tubes? I would check torque on them.
No, the tubes looked great and I didn't over torque them.
 

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Crank some more. Depending how long you waited between cranks, it may not have made it all the way up. The best bet for first crank is a real long one on a battery charger to keep voltage up. Pausing just allows the fuel to flow back down and deprime whatever progress has been made. I've never timed it but sometimes it feels like ages. LOL
 

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Well still nothing. Can I pour fuel in the cp3 and rail?
I wouldn't do that. You could get contaminants in there and ruin your injectors.
 

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Have a gauge to monitor the lift pump pressure before cp3.
Bump starter and let go lift pump should run for 20s seconds.
When stop running, pressure will drop at the beginning.
Keep repeat the bumping steps until the pressure holds at the normal lift pump pressure.
Now try to start.
 

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And what's the normal lift pump pressure.
Around 8 PSI iirc. That's at idle. As long as you have a few pounds of fuel pressure, your lift pump is not preventing the engine from starting.

Sent from my SM-G930V using Tapatalk
 

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And what's the normal lift pump pressure.
For stock in tank lift pump it’s around 9 psi at idle or at the end of 25 seconds (my truck) after bumping the starter.
If there is air in the system the pressure will drop soon after the pump stops running.
Then bump the starter again to repeat the air purging process until the pressure holds at 9 psi for a while.
The engine should be able to start now if air is your issue.

Side note:
I replace my 3 microns secondary fuel filter empty, without fuel inside.
Unusually after bumping the starter 3-4 times my engine will start normally.
It may need more times in your case.

After you get to the point the pressure holds, doesn’t drop right the way after pump stops running, crank it.
And the pressure should holds at 9 psi.
If it fails to start, then air in fuel supply system is not your issue.:wink2:
 
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