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Resolved 2G Issue EVAP / EGR delete & pressure in gas tank

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NFSPD_FL

Probationary Member
14
1
Feb 16, 2020
Melboune, Florida
I just picked up a 98 talon AWD. It has lots of excess pressure in the fuel tank. Trying to trace the issue I found it has an EGR delete / block off and an open line. What might be the issue causing the excess pressure? And can I just cap the open line?
 

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Solution
Can you be more specific on the fix, just some anyone else see where line or where exactly to look for.

If you don’t mind sharing.
In my case the delete was done incorrectly. Many of the deleted lines were just left in place and not removed. So there were lines all over most capped on both ends. It just so happened that one of the lines that came from just under the battery tray and ran up under the passenger front bumper was the gas tank vent line. So I uncapped it and it solved the problem for me.
The EGR being blocked off wont have anything to do with increased tank pressures. That open line is where we usually put a one-way check valve and route it under the wheel well. But considering it doesn't even have a check valve, it should bleed out all excess pressure all the time. But you're saying it's not, so you need to follow that line all the way back to the tank and see if it's kinked somewhere or blocked off. Might also be a good idea to take the rear seat out and inspect the fuel hanger assemblies for anything sketchy.

Also how exactly did you determine it has excessive pressure? Are you having a hard time putting fuel in it? Does the gas cap make a very loud and long hiss when cracking it open?
 
I actually have two open lines one small that appears to be a vacuum line. And one larger coming from the firewall pointing down. Both pictured circled in red.

Anytime I go to fill my tank as soon as I turn the gas cap tons of pressure comes out
 

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Nothing gas/vent line is routed through the firewall. As for the excess pressure. Maybe that hose got some crud in it and is blocked, could shoot air through the other end at the tank and see. Or the relief valve on the tank could be bad. Probably does not happen often but it is a mechanical part so definitely has a potential to. If it is then that means dropping the tank as it’s mounted on top.

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The one I labeled as open line under the hood would have one ADDED to it if they did the delete correctly to keep junk from going backward into the tank. The one I circled would be the oem vent valve.
 
The one I labeled as open line under the hood would have one ADDED to it if they did the delete correctly to keep junk from going backward into the tank. The one I circled would be the oem vent valve.


Is it one of these? And if so which one I got it like this with everything removed so I am not sure where each one was on the original install.
 

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Here is the delete thread that is used for getting everything removed the right way.. I also attached the pic labeling which line runs back and should be that line you have circled.

https://www.dsmtuners.com/threads/taboo-speed-shop-vacuum-diagram-and-removal-for-1g-and-2g.198327/


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Thank you very much you have been extremely helpful and I really appreciate it.

I looked over everything and still can’t quite decipher which one is which of those five little lines in the picture I posted.
 
Off the top of my head I believe two of those are brake lines, one is a fuel feed, one is a fuel return and the last one is the fuel vent line that would have went to the charcoal canister. Which is the one that is open right now. I would suggest it not be venting right beneath the battery for explosive reasons LOL. So maybe extend it and down. That’s after you fix the relief valve problem anyway.
 
The charcoal canister on the 2ga Gst is under the battery tray, not sure on the others but its not in or at the tank like the diagram suggests, there would be a vent running from the tank to that canister, you can vent it there and eliminate the canister if you dont have emissions.
 
The canister is located on the drivers side behind the front bumper, I circled it in the pic from my car. I would bet it has been removed though if they were as far as to put the egr plate and vent than line already. Just a guess.

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Yeah at first it’s hard to track everything down.. but I PROMISE you that the info is here and your original problem just sounds like a bad relief/vent valve. DM me and we can go from there instead of continuing this thread.
 
Hi, Looking for similar advice on doing a clean removal of my canister on a 1G NT. Would sure appreciate if someone could comment on my below approach to see if I am doing this correctly. Many Thanks.

Also, does this mod create any noticeable issues with the car? I know there will be codes thrown but any impact to driveablity?
 

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Dude ive read every one of the posts and none of them specifically address a 1g NT. Just hoping someone could look at my markups and confirm i'm doing this correctly and others experience doing this.
 
Can you be more specific on the fix, just some anyone else see where line or where exactly to look for.

If you don’t mind sharing.
In my case the delete was done incorrectly. Many of the deleted lines were just left in place and not removed. So there were lines all over most capped on both ends. It just so happened that one of the lines that came from just under the battery tray and ran up under the passenger front bumper was the gas tank vent line. So I uncapped it and it solved the problem for me.
 
Solution
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