2020 Denali with derringer threw fuel pressure code and limp

dracing70

SH--- GETTING EXPENSIVE!
Jun 12, 2007
1,210
0
36
45
mantua, oh
Has anyone had issues with there L5p throwing a fuel pressure code and then limping with a derringer installed? I’ve had it installed for a few weeks and drove for second time today. After a hard acceleration it through a code reduced power and stalled at light. I reset codes and all is fine however is this common??
 

dracing70

SH--- GETTING EXPENSIVE!
Jun 12, 2007
1,210
0
36
45
mantua, oh
So temps are in the 20s currently. In terms of the fuel filter I only have 10k on the truck so in My mind the filter traditionally should be fine however you can never be certain with fuel sources.
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,065
4,736
113
Phoenix Az
So temps are in the 20s currently. In terms of the fuel filter I only have 10k on the truck so in My mind the filter traditionally should be fine however you can never be certain with fuel sources.

You should be changing it at 10k or less.
 

LBZ

Super Moderator
Staff member
Jul 2, 2007
9,901
148
63
45
B.C.
You should be changing it at 10k or less.
The fuel filter?
I always followed the filter minder and it was closer to 25 000 miles before it would even hit the teens for % remaining. Never an issue. 10k or less seems a bit premature to me. However in this situation I would change it to rule out the low pressure side being an issue.

If dude lives in the south I’d investigate a gelling fuel issue considering temps in the past week or so.
 

diesel-max

Haisley Never heard of her
Oct 20, 2011
172
16
18
IN
Filters are cheap, injectors aren’t. I change them every other oil change.

It definitely would be a great, cheap easy place to start.
 

clrussell

pro-procrastinator
Sep 23, 2013
5,903
358
83
The fuel filter?
I always followed the filter minder and it was closer to 25 000 miles before it would even hit the teens for % remaining. Never an issue. 10k or less seems a bit premature to me. However in this situation I would change it to rule out the low pressure side being an issue.

If dude lives in the south I’d investigate a gelling fuel issue considering temps in the past week or so.

agree on the fuel gelling.Hence why I asked about temps
 

Chevy1925

don't know sh!t about IFS
Staff member
Oct 21, 2009
21,065
4,736
113
Phoenix Az
The fuel filter?
I always followed the filter minder and it was closer to 25 000 miles before it would even hit the teens for % remaining. Never an issue. 10k or less seems a bit premature to me. However in this situation I would change it to rule out the low pressure side being an issue.

If dude lives in the south I’d investigate a gelling fuel issue considering temps in the past week or so.

I’ve seen it cause far too many issues when ran over 10k miles. Servicing them early stops most issues. I have 9k on my truck and it’s already down to 25% on the filter percentage.
 

beach_33

Member
Feb 18, 2008
704
0
16
des moines, IA
I Had a check engine late the other night after a couple hard accelerations. No reduced power though. I cleared the code on the derringer and all was good.
 

dracing70

SH--- GETTING EXPENSIVE!
Jun 12, 2007
1,210
0
36
45
mantua, oh
So here’s an update. Since my first post things have been ok till today. Almost home with temps in low 40s and check engine comes on. Power gets reduced however since I was close I limped it home. Get in the drive and I attempt to clear codes however this tine they won’t clear and truck will not start. Codes come up p2627, p228b and p228c. So after a few minutes of frustration and no success I unplug the derringer from under the hood on the two sensors and plug factory harness back in. I get in and then I’m able to clear codes and truck starts. We will see tomorrow how it runs however signs right now point to an issue with the derringer. Thoughts?
 

dracing70

SH--- GETTING EXPENSIVE!
Jun 12, 2007
1,210
0
36
45
mantua, oh
Honestly? IMO, that shouldve been the first thing you did to diagnose it on Friday.
I would have however on Friday it cleared up immediately with clearing the code so I was hopeful it was a fluke. Has anyone heard of similar issues with these units?
 

LBZ

Super Moderator
Staff member
Jul 2, 2007
9,901
148
63
45
B.C.
Y’all must have some shitty fuel down there. I used to run marked fuel straight out of the rig fuel tank and never an issue. And know many others that do the same up here issue free.