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Discussion Starter · #1 ·
How do I go about seeing if I have a bad or going bad/leaking cp3 pump??. I've lost 3-4 mpg right after I put in a fass pump and the jeep liberty fuel module. 100 miles a tank. Ive had everything I possibly could check 2 times over except the pump? Only thing I can think of. Seems to have a little diesel fuel caked on the bottom of but not sure

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Discussion Starter · #4 ·
Dang..none of that happening. RP is normal too. Just have a little bit of diesel fuel caked on the outside of it. No drips on the driveway. Just wondering if a seal is bad if it could make me lose 4mpg?

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I know your 4x4. But my 2wd the hubs started getting hard to turn by hand, and I lost about 3 mpg till I replaced them. Might jack it up and see how hard the fron wheels spin. Just a thought.

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Dang..none of that happening. RP is normal too. Just have a little bit of diesel fuel caked on the outside of it. No drips on the driveway. Just wondering if a seal is bad if it could make me lose 4mpg?

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not at all.... unless your puddling.
 

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Discussion Starter · #8 ·
Its an exact replica of the dodge fuel pump its just easier to take out the internals in the liberty one and use it as a fuel sender. I used it in conjunction with the fass lift pump
 

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Discussion Starter · #9 ·
I know your 4x4. But my 2wd the hubs started getting hard to turn by hand, and I lost about 3 mpg till I replaced them. Might jack it up and see how hard the fron wheels spin. Just a thought.

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Good idea, never thought of that :thumbup:
 

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Discussion Starter · #10 ·
Checked out my hubs and they are worn, wheels little harder to turn. Gonna have left and right put in this weekend so we'll see how my mpg does after

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Checked out my hubs and they are worn, wheels little harder to turn. Gonna have left and right put in this weekend so we'll see how my mpg does after

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I chaseed mine for 2 months and never thought to check the hubs until i was doing brakes. Its just one of those things that dont come to mind at first.

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both my front hubs were shot and i didnt know and i was getting about 2-3 mpg loss from it i just fixed them and my mileage has gone up def try that or look at brakes draggin especailly rears they like to stick
 

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Discussion Starter · #14 ·
Well currently the diagnosis is 25% bad torque converter and bad left side hub
 

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Check rotors for wear and damage same with pads or excessive brake dust inside wheel and could take off wheel and operate brake to see if it sticks or not and if they are , you might be able to just get away with greasing the pins so they don't stick and drag
 

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I know your 4x4. But my 2wd the hubs started getting hard to turn by hand, and I lost about 3 mpg till I replaced them. Might jack it up and see how hard the fron wheels spin. Just a thought.

Sent from my SAMSUNG-SGH-I747 using Tapatalk 2
Got my new ones sitting here waiting to go on.... Hoping this solves my fuel economy issue too.... My front left is done and the right is on it's way.

both my front hubs were shot and i didnt know and i was getting about 2-3 mpg loss from it i just fixed them and my mileage has gone up def try that or look at brakes draggin especailly rears they like to stick
I have lost about the same fuel MPG and I am hoping for the same result.. As soon as my brake parts arrive ill be doing it all...
 

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Discussion Starter · #17 ·
Got my new ones sitting here waiting to go on.... Hoping this solves my fuel economy issue too.... My front left is done and the right is on it's way.



I have lost about the same fuel MPG and I am hoping for the same result.. As soon as my brake parts arrive ill be doing it all...
Well let me know brotha because if it ain't that then may be the injectors. I'm changing my hubs, axle u-joints and the torque converter. Had my injectors tested. They're worn..the balance rate test came in at 3.5-2.5. Supposed to be at 6-8 before they're pretty much shot. But the others are way cheaper :thumbup:
 

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nwqrc how do you like the minimax mp8 stack? what kind of mileage are u getting to a tank of fuel?
 

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I cleaned my intake filter which wasn't even to dirty and my map sensor and wow I wish I would of earlier made my mileage shoot up on over head and so far seems to be doing wayyy better on fuel in the half a tank I have driven ... Def try cleaning map sensor mine was dirty and now deleted won't have problem again
 

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Discussion Starter · #20 ·
I cleaned my intake filter which wasn't even to dirty and my map sensor and wow I wish I would of earlier made my mileage shoot up on over head and so far seems to be doing wayyy better on fuel in the half a tank I have driven ... Def try cleaning map sensor mine was dirty and now deleted won't have problem again
The overhead isn't accurate and isn't instant mileage right on the spot. But cleaning that stuff will definitely help. It only helped mine like half a mile better
 
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