Bleeding air out of the fuel system

TTBOOST · Jul 10, 2017

I changed both fuel filters and now I am getting a low fuel pressure light and it's going into limp mode. Pretty sure I got air in the system what's the best way to completely bleed the fuel system of air?

DockRocker · Jul 10, 2017

TTBOOST said:
I changed both fuel filters and now I am getting a low fuel pressure light and it's going into limp mode. Pretty sure I got air in the system what's the best way to completely bleed the fuel system of air?

Did you follow the procedure in the manual? How did you do it?

Sent from my iPhone using Tapatalk

sootie · Jul 10, 2017

I do the lower filter first, cycle the key six times letting the pump time out each cycle. Start the truck and make sure doesn't stall.

Then change the upper filter. Repeat procedure above.

I've never had so much as a hiccup doing it that way.

DockRocker · Jul 10, 2017

sootie said:
I do the lower filter first, cycle the key six times letting the pump time out each cycle. Start the truck and make sure doesn't stall.

Then change the upper filter. Repeat procedure above.

I've never had so much as a hiccup doing it that way.

That's the way I do it.

Sent from my iPhone using Tapatalk

Jomax · Jul 10, 2017

I change both and cycle the pump 5-6 times. Never an issue with 110k on the clock.

Sent from my iPhone using Tapatalk

6.0 Tech · Jul 10, 2017

Did you tighten the lower filter all the way? Pretty common on the 11-16 trucks to be 1 turn loose. Havent had to work on a 17 yet, but im assuming the pump is similar?

Spatel23 · Jul 11, 2017

It is different
Filter isn't screwed on/off anymore

TTBOOST · Jul 11, 2017

Okay I first started having problems when I completely drained my water separator. Then it started saying low fuel pressure and going into limp mode. So I proceeded to change both filters and bleed the system as discribed above. But I was still having issues and wasn't sure if maybe there was another way to bleed the air out of the system. The filter under the truck did not want to come out at all and when I got it out the plastic on the front was warped pretty bad. Anyone came across this before filter only has 6,500 miles on it.

Spatel23 · Jul 13, 2017

That's def not normal
I have no idea what would be causing that but I'd guess weak low pressure pump.

TTBOOST · Jul 15, 2017

Need help diagnosing my issues guys truck keeps going into limp mode and I'm throwing two codes p0093 and and another for over boosting (forget what the code is exactly). Any help would be greatly appreciated

8WR_ZJ · Jul 15, 2017

Bring it to the dealer

Sent from my SAMSUNG-SM-G891A using Tapatalk

Squat and Poot · Jul 15, 2017

TTBOOST said:
Need help diagnosing my issues guys truck keeps going into limp mode and I'm throwing two codes p0093 and and another for over boosting (forget what the code is exactly). Any help would be greatly appreciated

use your warranty if you've checked your upper filter connects and the lower filter, make sure the gasket is set tight and flush on the lower filter

Changed my filters today no problem, primed 8 times after lower swap and then another 8 after upper swap.

TTBOOST · Jul 17, 2017

Well I've already installed some warranty voiding mods so I'm trying to figure this out my self. Is their any to test and see if it's my low pressure in tank fuel pump? I think that's my issue because when you cycle the ignition button and the fuel pump is priming the system you can hear the pump slowing down and speeding up like it's having a hard time running. I've double checked all the filters to make sure they arnt sucking air and bleed the system a couple times.

ckrueg · Jul 18, 2017

If your referring to the Mexico tune it's technically OEM right? So it shouldn't void the warranty lol

Sent from my SM-G930V using Tapatalk

TTBOOST · Jul 25, 2017

ckrueg said:
If your referring to the Mexico tune it's technically OEM right? So it shouldn't void the warranty lol

Sent from my SM-G930V using Tapatalk

Yeah, exhaust and intake also

TTBOOST · Jul 25, 2017

Does anyone know how many psi the in tank fuel pump runs to the cp4? And does the pump run wide open all the time or is it variable speed kind of like a returnless fuel system?