Long story short im borrowing my brother in laws 2006 3500 2dr lbz dmax. while he is away on his honeymoon. I MUST GET THIS TRUCK RUNNING Yesterday. Truck threw P0087 after pulling small hill but ran great. Local garage said to try a fuel rail pressure sensor.We Installed a brand new AcDelco pressure sensor,truck ran great until 3 days ago.Pulled small hill and truck died.pulled truck home and scanned again and only got P0087. Truck started but ran at about 300rpm with no throttle response. Local garage said its not getting enough fuel. Installed bosch injection pump from dealer.Truck now cranks but wont start.Tried putting fuel pickup into container and it took 10-15 sets of 15 second cranks and pump pulled a half gallon of fuel but did not start.Brother in laws friend found injector return kit and with all the cranking in the world im not getting a drop in the containers.I did do some scanning and my fuel rail pressure is 34-71 psi,the fuel rail pressure regulator duty cycle is only at 12-14%(was told it should be 20%).The truck has some form of chip i believe he has small multi position switch in center console.Truck does have larger intake and turbo piping.It also has fuel pickup pump and other small mods.Please any help is badly needed and greatly appreciated. I have access to a scan tool and can pull any data needed.Thank you all.
Dmax Guru Needed EMERGENCY HELP!!!(Master dmax techs or pros please)
- Thread starter 07DuallyDmax
- Start date
Have you tried changing the fuel filter? P0087 is low pressure which could be caused by a plugged fuel filter.Gotta start somewhere.
Did you take the truck off-road???
Lol
Don't answer that:roflmao:
I'm definitely no GURU or in the same planetary system of an expert, but no one has mentioned this yet
Have you checked all the fuel lines leading up to the engine and cp3? are you sure there's no pinch in a hose or air getting into the line somewhere..
sometimes I've heard that the hard line (fuel feed line) will collapse near the firewall by the frame somewhere...and that can cause these and or similar issues
Lol
Don't answer that:roflmao:
I'm definitely no GURU or in the same planetary system of an expert, but no one has mentioned this yet
Have you checked all the fuel lines leading up to the engine and cp3? are you sure there's no pinch in a hose or air getting into the line somewhere..
sometimes I've heard that the hard line (fuel feed line) will collapse near the firewall by the frame somewhere...and that can cause these and or similar issues
Nope all supply and return lines are in good shape. Local dealer service manager said i could eliminate all supply issues by putting fuel pickup in container filled with fuel but truck still didnt start.
So you've replaced:
The filter in the engine bay and the filters on the lift pump
Bosch injection pump
And a fuel pressure sensor....
What about the fuel rail pressure relief valve?
I guess you checked your return rates and used a return line test kit, but if you're not getting fuel to the injectors, they wouldn't return any...
You've checked all the supply lines for bends pinches and cracks, and pulled directly from the fuel pick up on the CP3 and nothing? Not even a hiccup?
Damn dude
Not to be stupid, do you have the fuel lines going to the proper places? I can't see why you wouldn't be getting fuel with a lift pump and a brand new injection pump...
Have you tried to pull the feed line with the lift pump running, just to see how much fuel the lift pump is moving???
And you did, or did not check the pick up tube in the fuel tank???
The filter in the engine bay and the filters on the lift pump
Bosch injection pump
And a fuel pressure sensor....
What about the fuel rail pressure relief valve?
I guess you checked your return rates and used a return line test kit, but if you're not getting fuel to the injectors, they wouldn't return any...
You've checked all the supply lines for bends pinches and cracks, and pulled directly from the fuel pick up on the CP3 and nothing? Not even a hiccup?
Damn dude
Not to be stupid, do you have the fuel lines going to the proper places? I can't see why you wouldn't be getting fuel with a lift pump and a brand new injection pump...
Have you tried to pull the feed line with the lift pump running, just to see how much fuel the lift pump is moving???
And you did, or did not check the pick up tube in the fuel tank???
In your original post you stated fuel rail pressure was 34 to 71 psi. Are you sure that wasn't 34 to 71 mpa? If it's 71 mpa then that is more than enough rail pressure to start & run.
i wish it was but it is only 34-71 psi during cranking and with key on engine off. Im starting to think ecm fault of some kind im at a loss.
Unplug your fuel pressure regulator and try it. If no change and your confident the fuel lines are good, hooked up correctly and all, you may have a bad Cp3 pump. Doubtful but it happens.
If you a pull a fuel line off downstream from the pump, you shouldn't be able to hold the pressure back with your finger while cranking.
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If you a pull a fuel line off downstream from the pump, you shouldn't be able to hold the pressure back with your finger while cranking.
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Where I usually start is by getting fuel straight to the cp3. I have a 5 gallon bucket with a pickup tube and a 1/2" clear hose I connect after the filter head. You have to get all the air out of the line which is why I use a clear hose. Once you get that right you will be able to determine if your problem is before or after the cp3. If it makes pressure work your way back to the tank until you find your problem.
we have taken off the drivers side fuel rail supply line and and cranked the truck and fuel just trickles out....before we replace the ecm i will recheck all of my fuel lines from the filter to the cp3
He has a lift pump. I ASSume he has pressure right to the Cp3 based on his earlier comments. If he has the lines hooked up right and no blockage then he likely has a Cp3 pump issue. That said he may want to check for debris in the FPR as it could also cause the low pressure issue.
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Has anyone ever had ecm failure create these symptoms.Is low fuel pressure regulator duty cycle enough to keep it from starting?Has anyone ever had bad bosch cp3 or regulator? im really at a loss with this truck. Great fuel up to back of new cp3 and no start.Another quick question can anyone post Key on engine off fuel data readings from a truck that starts and runs. like frpr duty cycle,desired mpa, fuel rail pressure.baro and maf voltages (I think my readings are off and a 5v ref driver is causing my no start and no fuel) any info again guys is greatly appreciated.Thanks to all that have posted so far every little idea helps
Unhook the wire leading to the fuel pressure regulator on the injection pump. By doing this, it let's the cp3 go wide open fueling. If it still won't build pressure, then it probably is not an electrical problem
Start with the basics, pull the supply line off at the CP3 and make sure you have steady fuel there. This will sound stupid, but are you sure the CP3 lines got hooked up correctly? They didn't happen to reverse teh feed and return did they? The return is the one on top pointing upwards, and the supply is the one pointing rearward. If it has fuel to it, take the hard line off at the CP3 and see if fuel comes out. If no fuel comes out of the CP3 high pressure side or the return side, a piece of debris got into the supply line and when you hooked it up it plugged the FCA(regulator). If you have fuel there but not at teh engine then you have a kinked line or the popoff is hung wide open. In that case you neeed to do a bottle test on it. Start with the basics FIRST! Quit looking at control issues and unplug the FCA and eliminate any chance of something else affecting it.