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Discussion Starter #1
How are we doing everyone,

I have followed these posts for years now but this is the first time actually posting. I have an 02 F350 7.3 with 403,000 miles on her. Purchased the truck from my father at about 230K; and he bought it from the dealer at 20K so I know exactly what has been done with the truck and what she has been through. A little background the tranny was rebuilt at 230K, it has the original HPOP, original turbo and injectors, pretty much every major engine part is original except the oil cooler. Now as for my issue with my baby she acts like she is running lean when i get close to half a tank. I can noticebly hear it loping and knocking as it gets closer to half. Now what makes me scratch my head on this is the tank has been dropped and the fuel sending unit is brand new motorcraft. The tank did have some crud in the bottom when it was dropped so i cleaned it real good let it dry out for a day or two before it was put back on. The fuel pump on the rail is fairly new aswell however it is an autozone pump. So if both pumps are new and the tank is clean of debris, what would make it run lean close to half tank? I tested how far i could get one day and just below half the truck actually ran out of fuel. I know the fuel guage works because I put the trip on when i fill it and when its at about half tank i fill it up and it only takes about 16 gallons to get to tip top ( I have the 32 gallon tank). So any advice here would be greatly appreciated I love this truck and will keep it far past 500k, the truck owes me absolutely nothing and I truely love it. Thanks guys. - Dylan
 

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You're going to have to drop the tank again. Something is sucking air at the halfway mark. Probably where the filter housing snaps together. You could do the Hutch mod and be done with it.
 
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Discussion Starter #3
It must be right? I didn't think i would have this issue with a new motorcraft sending unit and i was not the one who installed it my mechanic did it. I believe the sending unit comes as one piece correct?
 

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The symptoms you describe lean towards the fuel pickup foot in the tank being busted off. Did you do the work on the replacement of the fuel level sending unit? It is possible that if you had the work done by someone else that they reused the pickup foot (which gets brittle with age) and it broke off recently. 430k on original injectors is amazing, I would like to hear a buzz test on those to see if they are working properly. It wouldn't surprise me if they are on their last leg, but that doesn't sound like its your current problem.
 

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I would also agree with the above advice.
DENNY
 

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So both of your opinions point towards the issue being in the tank and that sending unit?
If your observations that it happens at 1/2 tank are correct, then it has to be something in the tank. The sending unit is "one piece" out of the box, but it comes apart. There is a plastic compartment that holds two screens at about mid height. The pickup foot usually is about 1/4 height, so when people complain that their truck has issues at 1/4 tank, it almost always is the pickup foot. No matter what it is, it has to be in the tank if the fuel level is the determining factor as to when the issues occur.
 

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Do a search on cutting the vent tube while you are in the tank. Takes only a few min and I now can add 4 more gal at fillip.
DENNY
 
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