i have a 2009 lmm duramax and it starts acting like the batteries are dead but they arent it clicks a few times then fires up a month ago it threw a code and the code was a p0191 and started knocking so i had it towed into the dealership they said my battery cable was loose and the disconnected the pigtail and plugged it back in so i went to start my truck up this morning after a cold night and its acting like a dead battery again clicks a few time then fires up i really want to know what it is ive read alot about ppl having the same problem but no one really had a solution ive read that it could possibly be my cp3, fuel rail pressure sensor, fuel rail pressure regulator, wire harness pigtail,harness fuel pressure swith, or possibly need a reflash. anybody have a fix or the same problem i really wanna get it fixed thanks.

 

any luck finding out what the issue was? Im having the same problem

 

I am also dealing with a similar issue. I have replaced both batteries twice. March and three weeks ago. seems to start fine fora week or so then it starts to act up. The climate control goes to default settings then it won't start sometimes. Looking at it yesterday found that it was only starting on one battery and charging one battery (driver side). unhook batteries then hook them back up works fine. Any input would be appreciated.

 

I'm having that problem and mechanic can't figure it out wants to throw parts at it did you figure it out

 

Did you figure it out I'm having same problem and would greatly appreciate any help

 

I put a new computer and changed all three mega fuses on fire wall plus new batteries in mine and it didn't fix it

 

It acted up at christmas. I noticed that when it acted up that it would only start from the driver side battery and only charge that battery. Unhooked batteries cleaned ground at passenger engine block then hooked them back up and have not had a problem yet. What would "reset" after unhook the batteries and hook them back up allowing it to draw off both batteries? So far this has been the longest with out it acting up since bought it March.

 

maybe dirty grounds

 

I'll try it thx