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Discussion Starter #1
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My LB7 started losing power last week. It feels like the turbo is not working. There are no codes, no black smoke and it starts and runs like it always did but with less power. It now has about the same power as my 4.7L Durango.

I don't have any aftermarket gauges, just the factory ones so I can't tell you how much boost there is. I was told if the turbo wasn't working I would have a hard time maintaining highway speeds and I would be blowing all kinds of black smoke. Neither is the case. No smoke of any kind.

I tried changing the fuel filter, that did not work.

It sounds more like a supercharger under the hood than a turbo. You know, that kind of whining sound? It sounds like it's sucking real hard for air. My air filter was dirty so I changed it. No change.

Everything under the hood is stock. I haven't done any engine work. I have owned it since 129,500 miles. It now has 149,500 miles. Injectors were not changed under factory warranty so I'm guessing they are original.

Any suggestions?
 

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Discussion Starter #2
Bump.
 

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Discussion Starter #4
No codes at all? Hmmm.......

Fuel in the oil? Fuel gelling?
Oil seems fine. Took an oil sample. Will have results in a week. I'm not making the connection between fuel in the oil and power loss. Explain please.

Don't think the fuel is gelling. Changed the fuel filter and it ran out like water when I emptied it. It's been as cold as -3 in the morning with no symptoms. It's actually warmer now when the symptoms started.
 

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If your injectors are shot they're more than likely to not be able to deliver the power they used to when they were once new. If there is fuel in the oil you have an injector problem.
 

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Discussion Starter #7 (Edited)
Quote: If your injectors are shot they're more than likely to not be able to deliver the power they used to when they were once new. If there is fuel in the oil you have an injector problem.

Ok. I get it. It very well could be an injector issue. It's definitely not weak injectors though. This problem started in one day. I guess I'll find out for sure when I get my oil sample back. I fully expect to have to replace my injectors but I really don't want to do it now. I'm putting a screen and subs in it next month. If I have to replace injectors that won't be happening any time soon.
 

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mine did the same thing so i took it to a local diesel mechanic and he ran the balance rates on the injectors and return rates they were fine it turned out to be a bad cp3 pump i had them replace it and my truck ran like new other than the fact that i had them put one off of a lly for more fuel now it sucks my fuel filter dry so its time for a pusher pump on the frame id say change the cp3(injector pump) and you should b fine the pump runs about 800.00 plus the labor fees is the worst part
 

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Anytime I've had bad injectors I get smoke. Never had a pump go though so I will try to remember that. I do have the Fass System on mine and am very happy with it.
 

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Discussion Starter #10
Sorry guys. Forgot to update. After a mechanic I know suggested it, I changed the fuel filter. After about 50 miles, problem solved. Filter only had 2,000 miles on it. Guess I got some bad fuel.
 
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