yes and can you get your hands on a tech 2? if so go into fuel system and command the pump to 160 mpa at idle. see if it gets there and maintains it for a few seconds. that will indicate if your pump is making pressure.
LLY: Still having Rail pressure problems
- Thread starter Cougar281
- Start date
Well, I tried it with EFI. It was able to hold 160MPa. The pressure problem starts to show up when the pulswidth gets over 2000-2100uS... Is it possible the pump is going and not able to keep up with volume?
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Crewcabmax had a similar problem. Whenever he put on any tune more than a tow, it would only hit about 11k psi. It actually ran better on the small tune. He replaced the CP3 I believe. Maybe PM him.
Ed
Just a thought.... maybe it is a little air in the fuel on the suction side of the lift pumps.
You could try to run the truck out of a fuel can and/or check the returning fuel for air bubbles.
You could try to run the truck out of a fuel can and/or check the returning fuel for air bubbles.
usually it is flowing and working properly than. but keeping up with bigger pulse width may surface a diffiiciancy otherwise not there. i am running 3100 us and cant maintain 23000, but with out lift pumps it will fall to 17-18000 psi atleast for the couple second runs i have logged. not sure for 13 seconds.
Running for a short time with the regulator won't hurt anything, right? I assume the ECM would adjust pulsewidth and timing accordingly? at 160Mpa (or 180 with the regulator unplugged) it sounds like a Powerjoke!
New Problem!
Well, I tried isconnecting the regulator... Truck sounded like crap! Anyway, rail pressure dropped from about 6,500 from 26,000+ to ~19,000. Problem is now I smell Fuel (in a fairly big way; had what appeared to be fuel steam coming up from the engine, and VERY strong fuel smell)! I looked everywhere I could. Around all the injectors, Injector fittings, all the rail fittings I could see, and I can't see any signs of a leak AYWHERE. Thing is one day a few weeks ago when a friend rode with me, I thought I smelled fuel at one point as well.... My best guess, since I can't see any signs of leaks, is that it's either the regulator or CP3 that's leaking in a spot I can't see (not that you can see much of either with the engine toghether!). :help:
Well, I tried isconnecting the regulator... Truck sounded like crap! Anyway, rail pressure dropped from about 6,500 from 26,000+ to ~19,000. Problem is now I smell Fuel (in a fairly big way; had what appeared to be fuel steam coming up from the engine, and VERY strong fuel smell)! I looked everywhere I could. Around all the injectors, Injector fittings, all the rail fittings I could see, and I can't see any signs of a leak AYWHERE. Thing is one day a few weeks ago when a friend rode with me, I thought I smelled fuel at one point as well.... My best guess, since I can't see any signs of leaks, is that it's either the regulator or CP3 that's leaking in a spot I can't see (not that you can see much of either with the engine toghether!). :help:
LLY right? Diconnect the FCA again and see if ya can spot the stream of fuel?
I have used this little trick for LB7 hi-psi injector leaks
X2 but DO NOT STICK YOUR HANDS in ther that amount of pressure will take your fingers off or worse
use toilet paper and stuff it around all your connection is a idea?Ok, as suggested by Eric, I cleaned the engine off with degreaser and such and let it dry (the FPR is shiney!). The drivers side was already nice and clean, probably from my cleaning that side of the engine after I replaced the Power Steering hose, and the P/S valve cover was actually clean except for around #7 which seemed like it may have been from exahust getting past the blocker plate. Then ran the truck twice for about 50 seconds. Smelled fuel again, although not as strong as last night, but the degreaser smell may have been mixing with it. What I smelled seemed to be coming from the rear passenger side, but I'm not positive. Since I didn't spray the filter housing, that could be where some of the smell was coming from. I couldn't see ANY signs of fuel. I'd think that fuel jetting out at 26kPSi would leave a fairly obvious "wet spot". Last night, it seemed like there was a fuel "steam" coming up from the valley (after hovering over the engine looking for signs of fuel, I stank of diesel), but again, I'm not 100% positive. My only guess is the CP3 and/or regulator, but I don't know since I can't see much of them... Any suggestions how to look?
a few weeks ago my rail pressure sensor got loose and covered the cp3/fpr and sprayed a little around the driver's side valve cover. maybe take some stuff off the top of the motor and look around for loose fittings?
i do like Sweetdiesel's idea with the toilet paper, but maybe something a little thicker (good paper towels or those blue 'shop towels') might be a little easier to clean up afterwards.
Is the new leak there with out the lift pumps on? could be a rubber line from the housing to the CP3?
good luck, i hate leaks...... i have another one now too...
i do like Sweetdiesel's idea with the toilet paper, but maybe something a little thicker (good paper towels or those blue 'shop towels') might be a little easier to clean up afterwards.
Is the new leak there with out the lift pumps on? could be a rubber line from the housing to the CP3?
good luck, i hate leaks...... i have another one now too...
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get a piece of cardboard to move around the engine to help find the leak, it will leave wet spots and keep your hands safe. This is how we do hydraulic leaks at work
I had never thought of this or the toilet paper idea - good calls.
Now about this wet spot you seek?
X2 but DO NOT STICK YOUR HANDS in ther that amount of pressure will take your fingers off or worse
Ya exellent call man!
Dont need any fingers or worse chopped by a diesel-jet
:angel:
IDK but is there a plug in the end of the Fuel Rail on that side leaking or a return line that isn't hooked up right. Lb7's have fuel through the ECM. Just running things through my head.
We have had numerous leaks at connections, not sure what causes it, but it seems like tightening them a 1/16 of a turn stops some of them.
We have had numerous leaks at connections, not sure what causes it, but it seems like tightening them a 1/16 of a turn stops some of them.
LB7s and LLYs both have fuel running through the FICM (fuel injection control module, also called the EDU - electronic driver unit), not the ECM.
I dyed the fuel (UV Dye) on Thursday, and made another run today like the one that initiated the heavy fuel smell. Got the same results; heavy fuel smell. I tore into the top of the engine, removing as much as I could to get the best view I could of everything without removing the turbo, intake, draining the coolant, etc. I can't find any signs of dye ANYWHERE. All of the injector and rail fittings are clean, dry and dye free. As much of the CP3 and regulator as I can see is dye free. I fabbed up a UV LED on a small "inspection" mirror to try to see parts of the CP3 that I couldn't see from above, and still NOTHING as far as I could see (not that I could really see much). I'm positive the fuel smell is coming from somewhere on the high pressure side as it only showed up when I ran it with the regulator unplugged resulting in 26k+PSi rail pressures (although a dew weeks ago I smelled a much fainter fuel smell when having some "fun" while runnin ghte PPE330 tune. So I'm at a loss now... Anyone else had similar symptoms?
If theres any diesel in the oil, it could fuel vapor coming out of the crankcase vent/pcv system drain on the front of the motor. Might not see any liquid though.
Huh? It's an LLY so the PCV "vents" into the turbo inlet
. Anywho, I did a "Fuel in oil" test sugested by another member (press dipstick on white paper and look for a "halo" around the oil. None was present. Just the oil spot.