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Discussion Starter #1
Hello night owls...I was window shopping and I got this little bit of info off a site talking about a J-line bypass....This is what they said:

"When upgrading to an aftermarket Adjustable Fuel pressure regulator The restrictive "J-Line" has to be bypassed so that fuel flows freely back to the tank without any fuel pressure spiking."

This "J-line" they refer to; is this the same thing as the J-tube people speak of removing when adding an upgraded fuel pump? Thanks for any info you have.
 

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100% Eurotrash
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yep. j tube j pipe j line....all the same little pipe. just drill out the small end, get all the shavings out, and put it back on.
 

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Discussion Starter #4
so what happens if you just completely removed the J-tube with a block off plate & stock fuel pressure regulator and fuel pump? I ask because this is what I did when rebuilt my engine and car barely runs...
 

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Certified Supra Nut :P
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The "J-tube" has nothing to do with an AFPR, just a fuel pump upgrade. It will make it so that you can not lower the fuel pressure enough when flow goes up (read, larger fuel pump). It's designed as a fail safe in case the stock regulator fails, there will still be enough fuel pressure to run the injectors. When installing an AFPR on a stock pump, you're most likely trying to increase pressure, so the J-tube is irelivant.

At any rate, you can remove it at any time with no ill effects. As long as the FPR, stock or aftermarket is working, the J-tube does nothing.

When installing an aftermarket fuel pump, its removal is required though.
 

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it shouldnt do anything, that J tube is just there as a fail-safe incase the stock fuel regulator takes a shit, if your car runs like ass if you took out the J-tube I would say maybe your fuel regulator vacumm isnt hooked up or the regulator took a shit, but I wouldnt know for sure...just a thought
 

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Discussion Starter #7
The strange part about the whole scenario that I happened upon accidentally is that I do have my F-Con hooked up....runs poorly with or w/out, but there are 3 wires running from the F-Con to the F-Con solenoid and if I unplug the green wire going from the F-Con to the solenoid she starts running great to a point....like this she runs extremely rich (the CO% and CO2 are about 7-8 times higher than legal) and in normal driving no problems but I can only give her about 85% throttle....any more and she starts sputtering and hesistating.

So I cant find any vacuum leaks & it appears that with my "rigging" described above that she is being flooded with fuel....any ideas on if this could be the fuel pump going bad or the FPR that is causing the actual problem...and anyone got a pic of the fuel regulator vacuum just to make sure I did connect it properly? Thanks.
 
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