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Discussion Starter #1
So i pit on an airdog2 165, last week and noticed a huge drop in milage. Like from 17 in town to around 10 and 22 hw to about 15... I have checked for leaks all over and nothing. I put in new stock air filter also. Truck has full egr delete 4" straigt. And efi by idaho rob. 1/2 cp3 inlet fitting. What could be causing this? Please help!
 

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Not sure I just put the same thing on my 09lmm and I gained about 1 mpg. Did you turn the pump up or leave it at what it was set at by the factory?
 

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Interested
 

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Cant you adjust the psi thru the airdog? might want to check that
 

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Discussion Starter #5
Yes you can adjust psi, i left it whwre it was set at 10psi which is stock i believe. Im not running tuning big enough to turn up the psi yet? What do you guys think?

UPDATE: changed air filter, added a fuel treatment, aired up tires, and nothing... Doing fuel filter And MAF cleaner today to see shat that does.
 

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Is it possible to connect the lines wrong and it still run
Like sending the fuel that's supposed to go to the tank to the motor
Only thing I can think of
 

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pretty sure ive herd of guys having to turn up the airdog's for psi, set way to low / starving fuel to the cp3
 

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King of Battle
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dont think it will make much of a difference but i thought stock was around 8 psi?
 

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It could be hooked up to the wrong line, but I think too much pressure can cause problems. Maybe the pump isn't running and causing extra work for the cp3?
 

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Hmm does airdog have a tube that pushes the air/bad fuel and water back into the fuel tank? My fass has one connected through the filler hose.

Only thing I can think of is if that line was switched, giving your engine bad fuel with water and air because the bad fuel is very foamy. Your stock fuel filter could be cleaning up the little fuel that it can making it useable for the engine.


Sent from AutoGuide.com App
 

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King of Battle
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doesnt the water stay in the fuel/water separator? hence why you have to drain it out occasionally?
 

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King of Battle
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i think that would cause no fuel mileage not enough pressure to keep the truck running. i would either say the air dog is turned up to high or not working, although it is a flow through design so even if it isnt working it wouldnt effect things unless you givin er hell, at least i would think
 

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i think that would cause no fuel mileage not enough pressure to keep the truck running. i would either say the air dog is turned up to high or not working, although it is a flow through design so even if it isnt working it wouldnt effect things unless you givin er hell, at least i would think
The cp3 would pull that air saturated fuel in it wouldn't need to be pressurized
Imo anyways
 

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King of Battle
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true at that point it would be getting more fuel through that line then what it would be had it be hooked up correctly. wouldnt that be causing other issues then? or would the stock filter help with the air?
 

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Are you reading the MPG through the DIC or hand calculated?
 

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King of Battle
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^^^I was gonn ask that too but i figured with the numbers having such a significant difference i thought it was irrelevant
 

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You never know what happens to the DIC when you start to add aftermarket stuff. Just more accurate to hand check it to make sure it is actually getting much worse MPG than before
 
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