I have a 06 LBZ with 54xxx miles. The only things the truck had done to it when i bought it was an Edge programmer and 4 inch exhaust. i returned the truck to stock on the programmer and removed it. A couple of weeks later the truck started to lose prime and when i got on the pedal maybe 3/4 the truck threw a low fuel rail pressure and loss of communication with PCM code and wouldnt allow itself to rev past 2000 RPM. in the days that followed it continually lost prime. I rebuilt the fuel filter housing and Shimmed the Fuel Pressure Relief Valve and still it continues to throw the same code and do the same things. What could be causing this and how do i fix it?
Low Milage LBZ with low rail pressure code
- Thread starter JaylanBurns
- Start date
Check the soft fuel line's on the top driver's side engine and on the frame rail next to the trans. Sometimes they heat up and get soft overtime and kink, cutting off fuel supply.
If you keep loosing prime and rebuilt the filter head, your filter head could be cracked too.
I don't know about the loss of communication with pcm. I would check connections and wiring.
If you keep loosing prime and rebuilt the filter head, your filter head could be cracked too.
I don't know about the loss of communication with pcm. I would check connections and wiring.
i had a built LLY at one point and had an extra fuel filter housing laying around from it. when i rebuilt it i replaced everything including the bleeder screw with the exception of the WIF sensor. i have no way of Monitoring any rail pressure and i have yet to check the fuel lines
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Now when i do get on it it the trans acts a little funny. Could this be because of this fuel problem or the fuel problem be a by product of the limp mode?
It could be related to the fuel problem. Fix the fuel problem and see if the trans problem goes away.
If you have and codes post them up. The guys on here will be able to help you more if you list the codes.
I just went down to the local auto store and had them run my codes and i got p0087 Fuel rail pressure to low, p0102 Mass or Volume air flow a circuit low input, U1003 No DTS definition Found, and U1016 loss of communication with power train control module. i had them clear the codes and turned the programmer back on the see if that made a difference. i made it a mile and the engine light came back on and it went back into a limp mode. i want back to the auto store and they checked the codes again and it was just the fuel rail pressure and loss of communication to PCM. i had them clear the codes and i made it about a hundred feet out of the parking lot and it came back on. i dont even have to give it excess fuel now.
i managed to find my old air dog 165 and glow shifts. Should i hook up the air dog and the fuel pressure gauge and run it to make sure i am getting proper fuel all the way to the filter housing? that would eliminate the kinked or collapsing line wouldnt it? i have shimmed the fuel pressure relief valve but should i just go ahead and get the plug? its only like $30. i went through and checked all the fuses and they all seemed good. The batteries are decently new and i cant seem to find a wiring issue anywhere. But i also noticed while looking at parts that one of the things the Trans Go JR fixes is the loss of prime problem. Am i taking a chance that this is trans related?
With that many codes definitely have a carbon pile test done on the batteries one at time, you'll more than likely find the passenger battery failing. A transgo will not fix what you have going on...
when i hooked he glow shift fuel pressure gauge to the truck it read that during the drive i got 8-10 psi in limp mode. is that normal or should it be getting more
the truck is bone stock as of now with only 4 inch straight pipe. i have an air dog 165 laying around i can put on it if it will fix it. the sensor went in the filter head where the bleeder screw goes
