Wrangler TJ Gas Overflow Fix

I’m running around 45psi steady and have an issue when I’m running under load. It sputters and runs rough. 5th gear is a complete no go until this issue gets resolved.

Any thoughts on where to start?

I’ve replaced both O2 sensors NGK. TPS is new. CPS is new. IAC is clean. No codes no lights.

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I’m running around 45psi steady and have an issue when I’m running under load. It sputters and runs rough. 5th gear is a complete no go until this issue gets resolved.

Any thoughts on where to start?

I’ve replaced both O2 sensors NGK. TPS is new. CPS is new. IAC is clean. No codes no lights.

View attachment 359513

This seems like the wrong thread to ask this, but maybe I missed earlier comments somehow related?
 
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Hey, sure, my story and images start on post #61 of this thread. A few comments later in that thread, I also link to this thread, where my first post is #376. I bought a cheap PVC cutter on Amazon and used that to trim the vent tube back to just about an inch from the wall of the tank.

And you're right. As you'll see in my posts, our early-model tanks do not have the same valve that needs sanding. But you'll also see that my problem was slightly different: I did not have the 'burp' problem; I was just getting clicked-out whenever my tank reached 3/4 full.

SSTJ, or any one else here - have you guys ever seen a plunger like the one in the photos I attached below? My '04 TJR has been having both the fuel overflow and slow fuel fill problems, ever since I installed a 2" OME lift in April. My mechanic had a tank from an '03 TJ in his shop so I pulled the plunger out and as you can see in the pics, it doesn't look like the plunger or ball set up that others have posted about in this thread. Any thoughts on if it'd be worth my sanding down the plastic guides which (in this case) are on the walls of the cylinder that extends into the tank, that the plunger rides up and down in? The part number on the (Mopar) tank indicates that it is from a '03 TJ.

Thanks in advance for any thoughts/suggestions, this problem has been a PITA for the past 5 months. Was very glad to find this long and detailed thread.

Inside tank.JPG


Plunger.JPG


Plunger2.JPG
 
SSTJ, or any one else here - have you guys ever seen a plunger like the one in the photos I attached below? My '04 TJR has been having both the fuel overflow and slow fuel fill problems, ever since I installed a 2" OME lift in April. My mechanic had a tank from an '03 TJ in his shop so I pulled the plunger out and as you can see in the pics, it doesn't look like the plunger or ball set up that others have posted about in this thread. Any thoughts on if it'd be worth my sanding down the plastic guides which (in this case) are on the walls of the cylinder that extends into the tank, that the plunger rides up and down in? The part number on the (Mopar) tank indicates that it is from a '03 TJ.

Thanks in advance for any thoughts/suggestions, this problem has been a PITA for the past 5 months. Was very glad to find this long and detailed thread.

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View attachment 361685

I’ve not seen one like that. Could the tank have been from something beside a TJ?
 
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SSTJ, or any one else here - have you guys ever seen a plunger like the one in the photos I attached below? My '04 TJR has been having both the fuel overflow and slow fuel fill problems, ever since I installed a 2" OME lift in April. My mechanic had a tank from an '03 TJ in his shop so I pulled the plunger out and as you can see in the pics, it doesn't look like the plunger or ball set up that others have posted about in this thread. Any thoughts on if it'd be worth my sanding down the plastic guides which (in this case) are on the walls of the cylinder that extends into the tank, that the plunger rides up and down in? The part number on the (Mopar) tank indicates that it is from a '03 TJ.

Thanks in advance for any thoughts/suggestions, this problem has been a PITA for the past 5 months. Was very glad to find this long and detailed thread.

View attachment 361683

View attachment 361684

View attachment 361685

I have never seen one like that, but then again my only experience has been with my 97.
 
I’ve not seen one like that. Could the tank have been from something beside a TJ?

Thanks Fellas, yeah I was wondering the same thing myself. Here's a pic of the tank, and the part number on the side of it. I Googled the part number and it seems to line up with tanks for '03-'04 TJs.

I haven't dropped my own tank yet ('04) but I assume it has either the ball or plunger set up that most people have talked about on this thread so far.

The plunger set up on this tank in the photo seemed to have smooth sliding action, fwiw. I'm wondering if I should just install as-is and see what happens? Guess I can't make things any worse?

Also, not sure if it's related but I have been throwing EVAP error codes for small and large leaks over the same time frame as the fuel fill issues, starting after the lift install. I had my local shop smoke the EVAP system, replace the charcoal canister and solenoid - none of which solved the error codes or fuel fill issues. I am wondering if it's related to the plunger being stuck in the 'open' or 'half open' position?

Had a guy tell me that the way you know your TJ is running is if the check engine light is on. I'm starting to think he's right...

IMG_2108.JPG


IMG_2109.JPG
 
Thanks Fellas, yeah I was wondering the same thing myself. Here's a pic of the tank, and the part number on the side of it. I Googled the part number and it seems to line up with tanks for '03-'04 TJs.

I haven't dropped my own tank yet ('04) but I assume it has either the ball or plunger set up that most people have talked about on this thread so far.

The plunger set up on this tank in the photo seemed to have smooth sliding action, fwiw. I'm wondering if I should just install as-is and see what happens? Guess I can't make things any worse?

Also, not sure if it's related but I have been throwing EVAP error codes for small and large leaks over the same time frame as the fuel fill issues, starting after the lift install. I had my local shop smoke the EVAP system, replace the charcoal canister and solenoid - none of which solved the error codes or fuel fill issues. I am wondering if it's related to the plunger being stuck in the 'open' or 'half open' position?

Had a guy tell me that the way you know your TJ is running is if the check engine light is on. I'm starting to think he's right...

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Was a body lift involved or just suspension? A body lift involves the filler hose but a suspension lift should be completely unrelated.
 
Was a body lift involved or just suspension? A body lift involves the filler hose but a suspension lift should be completely unrelated.

Thanks, I put a 2" suspension lift on, and simultaneously removed the 2" body lift that the previous owner had put on. I replaced the body mounts/pucks with OEM spacers and replaced the fill neck with a OEM Mopar unit at the same time. That fixed the slow fill problem for about 2 wks, but then the same issues started back up again.
 
Thanks, I put a 2" suspension lift on, and simultaneously removed the 2" body lift that the previous owner had put on. I replaced the body mounts/pucks with OEM spacers and replaced the fill neck with a OEM Mopar unit at the same time. That fixed the slow fill problem for about 2 wks, but then the same issues started back up again.

Ah. Well the timing does make it seem related but it sounds like you would have checked the new filler hose by the time you got this far into it. I would probably have suspected the hose got kinked or something.
 
Thanks Fellas, yeah I was wondering the same thing myself. Here's a pic of the tank, and the part number on the side of it. I Googled the part number and it seems to line up with tanks for '03-'04 TJs.

I haven't dropped my own tank yet ('04) but I assume it has either the ball or plunger set up that most people have talked about on this thread so far.

The plunger set up on this tank in the photo seemed to have smooth sliding action, fwiw. I'm wondering if I should just install as-is and see what happens? Guess I can't make things any worse?

Also, not sure if it's related but I have been throwing EVAP error codes for small and large leaks over the same time frame as the fuel fill issues, starting after the lift install. I had my local shop smoke the EVAP system, replace the charcoal canister and solenoid - none of which solved the error codes or fuel fill issues. I am wondering if it's related to the plunger being stuck in the 'open' or 'half open' position?

Had a guy tell me that the way you know your TJ is running is if the check engine light is on. I'm starting to think he's right...

View attachment 361825

View attachment 361826

I thought the '03's/'04's had the metal ring to hold the fuel pumps in.

Thats interesting. The only two kinds I've seen are the later models that people file down and the early models that don't appear to be removable. I found this in a junk yard in Georgia and was going to pull the plunger until I found out it was the early model type.

IMG_6594.JPG


IMG_6608.JPG
 
I thought the '03's/'04's had the metal ring to hold the fuel pumps in.

Thats interesting. The only two kinds I've seen are the later models that people file down and the early models that don't appear to be removable. I found this in a junk yard in Georgia and was going to pull the plunger until I found out it was the early model type.

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Just did my 30k '06 last week. It has the steel ring.
 
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Thanks to all who contributed to this thread. I had the dreaded gas spit back issue when filling on my 2005. Decided to fix it properly. Also decided to put a new fuel pump in while I was at it. Dropped the tank and checked the check valve and it was tight like everyone sees. I used a Dremel to sand down the numbs and put it back in. I replaced my fuel pump while I was in there. Clearly the old one had been replaced already in the past but I went ahead and installed a new one. Got the Bosch as recommended on here. Super easy install. Took me maybe 2.5 hrs start to finish. Even took a break in the middle to drink a Coke and contemplate life. Nothing difficult. I pumped out all the gas with a Tera pump before fixing the check valve so I installed the tank empty. I did write the date and miles on the pump and the tank. Also sprayed a little lube on the locking ring to make it easier to tap on. Pump works great and most importantly, no more fuel spit back on fill up!!

Thanks for the thread!!
 
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Irritated. I thought I could buy myself some time but no. Just did my first fill up after the "temporary fix" and it sprayed gas all over...as if I didn't go through the hassle (the thing was damn near glued on) to change out the filler hose at all. I am glad this resolved the issue for some. It did not provide value in my case.

Bottom Line. In case you have read through the thread this far and are still contemplating the filler hose change (thinking it might be solved with less time output)...my opinion is spend your time learning how to drop the tank
 
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You can win if you forget about the temporary fix and do the real fix, as this thread suggested back on page 1. Sure, it's more work, but it works.

I had the gas burp problem for a long time, and then one day it switched over to gas block. That's what pushed me to finally drop the tank and really fix it, and life is much better now.
 
Ugh. Super irritated. I just did my first fill up after the "temporary fix" and it sprayed gas all over...as if I didn't go through the hassle (the thing was damn near glued on) to change out the filler hose at all. Sigh. I can't win with this machine.

I cut the GM Hose and took the flipper thing and put it in my Jeep hose. Works much better now