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badburban
09-24-2007, 17:49
Got a question on my 04 LLY. Put a lift pump in it and after that I almost immediately developed a very large fuel leak on the back side of the motor on the passenger side. It can probably easily leak a 1/2 gallon of fuel in about 30 seconds. The truck still runs no problem but it leaks fuel all over the place when its running. I checked the filter housing which is dry, checked the fuel rails and lines and all injectors and they are dry. Where every it is leaking from leaks all over the top of the starter. I just can't figure it out with all the stuff back there. Does anyone have any ideas or have some pcitures of fuel line routings that I can use to help troubleshoot. Thanks.

Josh

More Power
09-24-2007, 18:48
Follow the fuel path from the quick-disconnect lines above the left valve cover to the fuel filter housing and then onto the FICM, and then to the hi-pressure pump. Use baby powder on those areas if you can't see the wetness. Where the powder wets out is the leak source.

There have been reports of leaking rubber lines.

Jim

willypr94
09-25-2007, 20:00
dropped mine by the dealership 2 days ago with fuel leaking down back of motor on passenger side. Also fuel is collecting on top of intake, curious to see how the 200k warranty is going to help. No reply from them yet I'll let you know. Also noticed heavy black smoke when stepping down hard on throttle, couldn't even see the convertible next to me.

badburban
09-26-2007, 05:55
willypr94,

Really, same symptoms I have, Id be interested to know what they come up with if you don't mind letting me know once you find out. Thanks

I started pulling mine apart last night and have alot of fuel in the valley and then pouring down the pass side of the back of the block. I just can't imagine a fuel supply hose on the low pressure side of the injection pump let loose though. Someone was telling me that these injection pumps have like a overpressure pressure relief and they thought that was it. Now Im not sure as I dont know alot about the CP3 pump but at the same point I dont know how they could just vent it open like that I would have though the fuel would have had to gone to the tank or something. I thought about adding some dye to my fuel to find the source of the leak.

Anyone have any other ideas or good info... Thanks

Josh

DmaxMaverick
09-26-2007, 07:20
I hate to speculate right before you actually see it, but the FPR (Fuel Pressure Regulator) can leak, and has on some engines. Many times tightening takes care of it. It is located at the back of the HP pump. When a pump develops a leak (very rare), it will often be into the crankcase, and not external. I think you will find a connector or component connection leaking. A fuel line on the suction side shouldn't leak much. If the leak is large enough to pour fuel like you say, it would be a big enough hole to stall the engine from lost prime.

badburban
09-27-2007, 21:24
Well i figured it out... Got her torn down and found out the return line off of the injection pump that goes back to the supply line had popped off of the injection pump. So i put everything back together with some screw clamps instead of the factory stuff. Put it all back together and test drove it tonight and all is well.

willypr94
10-01-2007, 09:18
Dealership called and said they were replacing a busted injection pump and were checking the injectors to see if they needed replacing. i'll let you know what else they found after they call back.