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Discussion Starter #1
Hey everyone, I just had the injectors replaced on my '04 at the dealership and they also put in a new filter and flashed the computer with updates. Since then my overhead computer shows a loss of approx. 4-5mpg. I was avg. around 18-20mpg and now I'm getting 14-15mpg. Otherwise the truck runs better and has a little more power. I also had a lift pump replaced last November. What could be causing this? Injection pump? I think I'd be getting better not worse mpg. No dio. codes show.

Thanks, JTDC492:beer
 

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have you checked it by hand? i never trust that overhead
 

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Over head is a joke..... You would think @ 30,40,50k these trucks would have a gauge that works....... I guess as soon as toyota builds one, A couple years later dodge will bring up the rear....AS USUAL This gauge should work off GPS for accuracy and a virtical tube in tank . Not rocket science, just to hard for DC
 

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JT, I think one of the updates for the '04 included an update that made the overhead "more accurate". (if you can say that about that thing). Anyway you may be seeing more realistic numbers now, or it may be off to the minus side. Bottom line hand calc and see what you are really getting. I wish my overhead was close to real, it hangs around 23 - 25 most of the time, actual is more like 18 - 20. Also I had a single injector changed and lost mileage for several tanks of fuel afterwards (16mpg empty). Then it started climbing to the great numbers I get now.
 

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have you ever had the truck flashed by the dealership before? If not then I bet your gonna see lower numbers because now you have the same set up the 610s do which usually don't get the same fuel economy??? If yours is an early 04 at least......
 

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My overhead has ALWAYS been 2-1 MPG optomistic. Don't trust it.
 

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just an average

FYI about the over head, it is an average reading. the longer you let it calculate the less accurate it is. Just keep resetting it, at least every tank if not every 1/2 tank. I still check my by hand, but my over head reflex my driving style:peelout

just my $.02
 

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Discussion Starter #10
I just checked by hand and came up with 15.5mpg, which was real close to what the console showed. I talked to the dealership and they said that they can't do anything to reverse the updates and don't know what the updates are exactly, in otherwords I'm SOL. Hopefully the mpg does climb back up to where it was.
 

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From what I understand when you replace the injectors it isn't going to get as good of fuel milage for a while and will increase as the injectors get broken in.
At least thats what I've heard:thumbsup
 

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If i fill up, reset the overhead, and don't touch it again until the next fill up, my overhead is always within .2 - .5 mpg. I've even had it dead on quite a few times. Guess i am one of the lucky ones.
 

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I reset my trip odometer after every tank. You should be able to tell if your mileage has dropped that significantly. I pretty much average 510 miles before a fill up. I you were loosing 4-5 miles per gallon that number you be decreased by 100-150 miles.
 
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