P0087 fuel rail pressure low limp under high loads

[Mark Rinker]

Root cause: excessive return flow from the injectors due to wear.

Cheap fix: Kennedy Custom ECM programming

Expensive fix: 8 new injectors

Where does "Lift Pump" fall into that continuum?

JK with all respect due, anyone that takes the time to re-read this nearly seven year long thread would deduce that it certainly WAS a long and winding road finally leading to 'root cause'. I'm glad that you stuck by your customers and finally found a programmatic solution for this problem! Congrats.

Glad its solved. Hope GM has/will incorporate better ECM programming in the future to allow for a wider range of injector return rates as the injectors wear over time.

[Kennedy]

Where does "Lift Pump" fall into that continuum?

Mandatory for any Duramax in my opinion and experience.

[Mark Rinker]

Mandatory for any Duramax in my opinion and experience.

Your opinion is welcomed, your experience is deep and wide. Please explain

• Why GM has sold millions of units since 2001 without a lift pump;
• What is the accelerated outcome of not having a lift pump - i.e. premature CP3 pump failure, premature injector failure, global warming, etc;
• Why it took seven years to arrive at a programmatic solution for the P0087 error code, if adding a lift pump was not the solution.

Curious, as I've been since 2009 when I first started this thread.

[Kennedy]

http://www.kennedydiesel.com/docs/Du...ift%20pump.pdf

[Sirgrinalot81]

New to the diesel life and having some issues. I have an 2009 lmm 95000 miles keeps throwing p0087 and is going through fuel filters like 1 a month. Totally stock. Also have a lot of water in the fuel. Located in Kansas. I just ran it almost empty put seafoam in it and filled it up. Think I got a bad tank of fuel from caseys. Before it was throwing p0088 instead of the p0087. Any help is appreciated thanks

[Kennedy]

New to the diesel life and having some issues. I have an 2009 lmm 95000 miles keeps throwing p0087 and is going through fuel filters like 1 a month. Totally stock. Also have a lot of water in the fuel. Located in Kansas. I just ran it almost empty put seafoam in it and filled it up. Think I got a bad tank of fuel from caseys. Before it was throwing p0088 instead of the p0087. Any help is appreciated thanks

What I would recommend is a small bottle of FPPF Fuel Power to dry things up in your tank and then find a better fuel vendor or who spiked your tank.

From there my Tech Tips have the answers. On a daily basis I am "fixing" this with my pumps and tuning and will add that I am now hearing from a lot of "second round" guys who did the injectors and repeated shortly after or even immediately. The solution is still the same, still highly effective, and to me it just makes sense to do something that improves the system rather than just replacing parts with same.

P.S. I would NOT get hung up on water separators as many seem to be doing. You are one of the very few that has ever found any water in their systems

[CoyleJR]

I just returned home from four months on the road pulling our 38' 5th wheel. The truck and 5th wheel have a combined weight of 23,800 lbs and the temperature was often well over 100 degrees. My truck is a 2006 LBZ with 240,000 miles and this is the first time it has shown P0087 code. I found that if my fuel tank level was below half a tank, the temperature was over 100 and the truck was working hard pulling a steep grade it will throw P0087 code. I was able to repeat this problem code several times and fix it by opening the valve on my second fuel tank and adding fuel to the primary truck fuel tank. For 240k miles I have always kept the truck tank full by gravity feed from the secondary tank. This trip was the first time I let it get below half a tank of fuel. A full fuel tank must cool the hot fuel returning from the motor and that cool fuel keeps the truck from showing the P0087 code. I realize that there can be several causes for a P0087 code to show up but on my truck high fuel temperature seems to be the cause.

Additionally, I keep the small fuel cooler radiator in front of the fuel tank very clean and I am now considering installing a second fuel cooler on the right side of the truck.