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gimpyhauler
03-25-2014, 14:42
Ran over to the coast this morning. On the way back, I was traveling 65 and came upon a long tall hill. All of a sudden, I slowed to under 30. I had no throttle control. It seamed that if I put my foot in it it would slow. Once I crested the hill, I got back up to speed but not because my foot was in it. It continued. When I got to a light and tried to get going again, after an onramp, I couldn't get to speed. Thankfully I was almost home. Flat from there and got home at speed (35) limit. It started about 20 miles from home.

Please someone tell me it's a clogged fuel filter? It's only been about 4000 miles since it was changed. But it just seems like that is what it'd be. My truck has been rock solid since I bought it.

Could it be anything else?

rapidoxidationman
03-25-2014, 15:50
Got codes?

Sounds like your hauler got gimpy sorry, I couldn't resist... and went into limp mode. P0087 comes to mind.
http://www.thedieselpageforums.com/tdpforum/showthread.php?t=35292

gimpyhauler
03-25-2014, 21:04
Okay, so I'm a newbie on codes.

To start with, my truck coded when I replaced my batteries. I have not clear it yet because I didn't know how.

How can I produce/read the codes? Do I need a scanner/code reader? Maybe it time to get one.

I really appreciate this help. If you don't mind helping a gimp (Smile) tell me how to get the info I need to fix this problem.

Kennedy
03-27-2014, 11:52
Start with DTC's as mentioned.

Diagnosing the fuel filter/system restriction is easy if you have one of these:


http://www.kennedydiesel.com/images/Dmax-fuel-filter-rest1.gif

gimpyhauler
03-28-2014, 12:44
Kennedy,

I got a reader and it is a P0087 code. When I replaced the batteries it reset my fuel filter use. So it's just time to replace the filter. I have them in stock thanks to you already. So that's a job I can do without a doubt. Now I even have the special water separator wrench to do it right.

Now on to the lift pump. Other than increasing the flow rate and being able to use it to diagnose the condition of the filter, what does it do for me? Is the standard pressure not enough for regular use or are their other advantages?

I'm going to your website to look at the lift pump but perhaps others could benefit by knowing why we need/want one.

Thank you my helpful friend.

PS: My build sheet says I have a block heater. I've never been able to find it. Then I went to youtube to see how to replace the fuel filter. The video I watched, the guy removed the wheel well to better see and video tape. There was the truck owner's block heater he didn't know he had. Now I know where to look when I replace the filter.
/\/\/\/\/\

rapidoxidationman,

Thanks for the help. Because of you, I went ahead and bought a reader so I never have to be totally ignorant of my truck's codes. Thank you. You were spot on with the P0087 gimpy code. Smile.

Kennedy
03-28-2014, 16:40
The Duramax does not have a lift pump. It uses the transfer pump on the main CP3 injection pump (in the valley) to supply fuel to the HP side of things.

This means the entire rear part of the fuel system is under reduced pressure aka suction/vacuum. With this setup, any little leak can allow air in. This can cause a loss of prime etc. Additionally, we find that as the fuel is warmed and spends time in the lines it begins to outgas or "fizz" in the lines. Air in fuel is never a good thing.

Adding a lift pump flips the pressure from below atmospheric to above atmospheric. This helps keep the fuel liquid and the filter air free so it can do a better job.

Some also find that a lift pump helps responsiveness and mpg. I believe that the gentle "push" from a lift pump helps the regulator do it's job more precisely keeping the rail pressure on target much better.

As for the block heater cord, that was one of my first Tech Tips showing where it was located and how to route it down to the tow hook area for easy access without pinching under the hood or scratching the truck.

gimpyhauler
03-29-2014, 17:52
After looking at the product page and installation docs, I'm concerned whether I can install it myself. If I have to remove the tank, that's perhaps more than I want to do in my driveway. I'm handy with a wrench but these old bones and bad shoulders just don't want to take on too much.

What do ya think? I'm fairly sure it's my filter this time around but I'm hoping this will be my last truck I have to buy. So I'm willing to help the heart of my truck as much as reasonable.

I'm starting to cluck.

DmaxMaverick
03-29-2014, 19:45
Tank removal is only necessary if you are replacing the sender/pick-up, or associated lines. Adding a pump/filter in the area can be done in-line, and is most often. Unless you suspect a needed repair between where you intend to interrupt the fuel line and the tank plumbing (or increasing HP to 500+), there's no need to remove the tank.

On another note:
It's easier to remove the bed than drop the tank.

gimpyhauler
03-30-2014, 11:42
DMav,

Thank you. Now I feel confident enough to add the pump.

It's actually fun getting back to turning a wrench. I was a VW mechanic right out of high school, back in the days when the dealerships were Porsche and VW together. When we still had regular carburetors and could do most repairs with a handful of tools. My wife doesn't appreciate the black fingernails though. My entire tool box with tools cost me $243 (Sears Credit)

Thanks again.

rapidoxidationman
03-30-2014, 13:57
http://upload.wikimedia.org/wikipedia/commons/8/8d/Disposable_nitrile_glove.jpg
A box of 100 for less than the price of a six pack of good beer...

Your hand's skin will thank you. So will your wife.:D

DmaxMaverick
03-30-2014, 15:22
Freelance proctology? I'd have never guessed.....

gimpyhauler
04-01-2014, 19:35
My wife always gets a little crazy over my dirty hands. Just going through the gate requires washing my hands. Not dirty hands, just that she knows I touched the galvanized gate. I bought two boxes of those blue gloves just for the grease and oil work associated with equipment.

Waiting for my next delivery. Thanks.

Kennedy
04-02-2014, 08:12
The LBZ's you can access the tank supply fitting without dropping the tank. If it's not too rusty it will come free.

As for the gloves that is a great idea and has become a necessity for me these days. I've always thought that I had somewhat sensitive skin, but recently started breaking out really bad. Looked like poison ivy type stuff. Finally broke down and saw a dermatologist. They did some patch testing and hit on:

potassium dichromate

cobalt hexahydrate

bisphenol epoxy a

In other words no need to test any further. The chromate is the smoking gun. That's just about everything metal :(

I think what built the reaction (contact dermatitis) is years of wearing cheap unlined leather gloves. They are typically chromate tanned so add sweat or water and ...

chessy56
04-07-2014, 14:13
Similar situation: installing Kennedy lift pump, only I had to replace the sending unit too. DMax had the right idea- lift the bed! Easy to suspend in the garage with a 1 ton chain hoist. Working on the top side of the tank sure was a blessing!