Fuel pump

hidden1

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#16
No codes at all.in fact I have a odb2 /elm program on phone that shows a normal fuel trim reading too..
I did correct s emissions Nldp recently but it has cleared fully after so many runcycles.
I literally drove it all over with a half tank an observed this fully once it gets to that point.low fuel .did several test runs..if I stop faster it can miss hesitation an stay at 670rpm[only under low fuel in tank]..
 

hidden1

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#17
I literally drove it all over with a half tank an observed this fully once it gets to that point.several test runs..if I stop faster it can miss hesitation an stay at 670rpm
No vent valve so I'm told ,an a new gas cap too..
Those darn filters can get clogged in the tank I'm sure .
U never see a issue at all when fuel level is high !
 

hidden1

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#18
I think im gonna put another fuel pump/ module/assembly/unit in it an clean out any trash in the tank.I did use several treatments in tank that may have dislodged any gunk or trash in it.
Any other ideas to look at ,or try , including blow the lines out ?
 
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#19
some thoughts -
a 15yr old truck and assuming there is a correlation between tank level indicator (1/8) and amt of fuel (Xgallons) seams wishful.

Could a incorrect pump installation - module position marks not aligned? Trapping flaot rod.. does the low fuel warning ever come on - maybe when a hard stop?

A problem with strainer inlet filter .

Anyway I think the answer will be in tank as you inspect pick up.
 

hidden1

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#20
I haven't had a problem till last few weeks an had it since NOV..I don't know of last pump change out either .

Nvm: 45
 
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#21
Did not know it was a recent issue - that would have me agree with you replacing module - would not remove it to look without replacing it - too much time and work.

I will add it is suggested to get a OEM pump - aftermarket has us shaking our heads no no .
 

hidden1

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#22
Did not know it was a recent issue - that would have me agree with you replacing module - would not remove it to look without replacing it - too much time and work.

I will add it is suggested to get a OEM pump - aftermarket has us shaking our heads no no .
 

hidden1

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#23
What is the best brand that's not over high on cost?..
On putting in new how do I know the correct mark to place it at ,I see many putting mark on old one before removing but not sure mine is where its supposed to be before removing it..
Also what's the best technique to use to clean out the tank once off ?
 

nickb2

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#24
Well then, you are left with only a few options, either a gas leak externally. Or a leaking TBI internally or a new fuel fump unit.

Unless I am missing something here.

Since I now know you have live data capability, can you post the fuel trims in snapshot format?

but I think this will be a useless endeavor with a 17psi drop.

If the FPR is shot, your fuel trims will be out of whack all over the place as the PCM tries to correct the algorithm.

No codes at all.in fact I have a odb2 /elm program on phone that shows a normal fuel trim reading too..
So I would seriously start looking at a new fuel pressure tester, bad adapter or seal.

The fuel trims NEVER lie, and no codes to boot.
 

nickb2

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#26
Also what's the best technique to use to clean out the tank once off ?
Best technique from my knowledge is siphoning any OLD gas out, then flushing with fresh water for a few hours while you work on trying to find any cracks in the fuel lines. This is a plastic tank, right?
 
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nickb2

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#28
What is the best brand that's not over high on cost?..
There is none, just a hope and a prayer you did the job right. But I prefer the NAPA units.

Maybe the USA guy's can answer that question better than me. I don't know where your from. I always recommend OEM, but that depends on your budget.