TPI Tuned Port Injection discussion and questions. LB9 and L98 tech, porting, tuning, and bolt-on aftermarket products.
Sponsored by:
Sponsored by:

Deleted evap canister now tank line leaks gas!

Old 12-16-2014, 01:38 AM
  #1  
Junior Member
Thread Starter
 
Voltz77's Avatar
 
Join Date: Apr 2014
Location: Texas
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Car: 85' Firebird TransAm
Engine: 305ci TPI 5.0L
Transmission: 700R4
Axle/Gears: Posi 9 bolt differential 3.27
Deleted evap canister now tank line leaks gas!

Today I took off the evap can and installed a home made cold air/ in fender intake mod, the mod was a success as I used the convenient square cut out that is located behind the canister. So I did some research here and a lot of people have said to cap off the 2 lines ( I did ) and either cap or put a fuel filter in place of the bigger gas tank line. Well I put a piece of cloth towel and stuffed it in there and took it for a 15 min spin. When I came back I checked the line and the cloth was SOAKED in gas.. I noticed my mpg dropped a tad or maybe I was being more heavy footed? My concern is, there any way to prevent the line from leaking out like this???
Old 12-16-2014, 06:50 PM
  #2  
Junior Member
Thread Starter
 
Voltz77's Avatar
 
Join Date: Apr 2014
Location: Texas
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Car: 85' Firebird TransAm
Engine: 305ci TPI 5.0L
Transmission: 700R4
Axle/Gears: Posi 9 bolt differential 3.27
Re: Deleted evap canister now tank line leaks gas!

I tried an inline fuel filter on the gas line and it seemed to have stopped the leak, I routed it in the fender wall where the pod filter now resides to reduce the hint of gasoline fumes, which aren't that bad really. Im sure on a hotter day it may be more pronounced.
Old 12-17-2014, 06:40 PM
  #3  
Supreme Member

 
8Mike9's Avatar
 
Join Date: Jul 1999
Location: Oakdale, Ca
Posts: 5,183
Received 42 Likes on 38 Posts
Car: 89 IrocZ
Engine: L98-ish
Transmission: 700R4
Re: Deleted evap canister now tank line leaks gas!

Evap lines should only be carrying fumes...unsure why a filter would stop your issue? As it is a blow through device.

Best recheck what you did...gas makes a big boom...people die.
Old 12-17-2014, 07:15 PM
  #4  
Junior Member
Thread Starter
 
Voltz77's Avatar
 
Join Date: Apr 2014
Location: Texas
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Car: 85' Firebird TransAm
Engine: 305ci TPI 5.0L
Transmission: 700R4
Axle/Gears: Posi 9 bolt differential 3.27
Re: Deleted evap canister now tank line leaks gas!

I understand the filter is a blow through device, but its designed to contain and stay soaked with gas IF the event occurs again. It hasn't so far. Why gas came through the line? I cant say, which is why I came here for an answer in the least an idea.
Old 12-17-2014, 09:49 PM
  #5  
Supreme Member

iTrader: (8)
 
TTOP350's Avatar
 
Join Date: Oct 2001
Location: Il
Posts: 11,686
Received 745 Likes on 505 Posts
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Deleted evap canister now tank line leaks gas!

Y not hook the canister back up but hide it up behind the bumper support like i did in the early 90s.
Old 12-17-2014, 10:08 PM
  #6  
Junior Member
Thread Starter
 
Voltz77's Avatar
 
Join Date: Apr 2014
Location: Texas
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Car: 85' Firebird TransAm
Engine: 305ci TPI 5.0L
Transmission: 700R4
Axle/Gears: Posi 9 bolt differential 3.27
Re: Deleted evap canister now tank line leaks gas!

Ive seen pics of it being bolted up upside down under there is that what you mean?
Old 12-18-2014, 11:40 AM
  #7  
Supreme Member

iTrader: (1)
 
racerx520's Avatar
 
Join Date: Jun 2007
Posts: 1,532
Received 7 Likes on 5 Posts
Re: Deleted evap canister now tank line leaks gas!

i just moved mine to hiding it the best i could under the tiny overhand at the front passenger corner of the engine bay. I have heard some people having issues after putting it upside down, and also heard of someone having some issues after extending the vacuum lines. basically i left my line length the same but tried to hide it a bit.
Old 12-18-2014, 12:05 PM
  #8  
Supreme Member

iTrader: (8)
 
TTOP350's Avatar
 
Join Date: Oct 2001
Location: Il
Posts: 11,686
Received 745 Likes on 505 Posts
Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Deleted evap canister now tank line leaks gas!

The wont work like they are supposed to if upside down.
The SLP kit comes with longer vac lines and electrical to move it across the engine bay. I havent had any problems with my lines being longer.
Old 12-18-2014, 12:24 PM
  #9  
Supreme Member
iTrader: (-3)
 
1991sleeper's Avatar
 
Join Date: Dec 2012
Posts: 1,184
Likes: 0
Received 1 Like on 1 Post
Car: 1991 firebird
Engine: TBI 305 (built)
Transmission: T5
Axle/Gears: 4.10
I removed mine and no gas ever leaked out
Attached Thumbnails Deleted evap canister now tank line leaks gas!-forumrunner_20141218_122345.png   Deleted evap canister now tank line leaks gas!-forumrunner_20141218_122355.png  
Old 12-18-2014, 05:43 PM
  #10  
Supreme Member

iTrader: (16)
 
Street Lethal's Avatar
 
Join Date: Jul 2003
Location: NYC / NJ
Posts: 10,464
Received 174 Likes on 152 Posts
Re: Deleted evap canister now tank line leaks gas!

Originally Posted by Voltz77
Why gas came through the line? I cant say, which is why I came here for an answer in the least an idea...
There is a pressure valve in the back behind the rear that relieves pressure buildup in the tank, check to see if that valve is faulty and sticks closed. Too much pressure will cause the fuel to be pushed out any fuel line available, including the charcoal canister line. If it happens again, you can also just get a vented gas cap, but some states don't allow that legally, so check...
Old 12-19-2014, 01:16 AM
  #11  
Junior Member
Thread Starter
 
Voltz77's Avatar
 
Join Date: Apr 2014
Location: Texas
Posts: 28
Likes: 0
Received 0 Likes on 0 Posts
Car: 85' Firebird TransAm
Engine: 305ci TPI 5.0L
Transmission: 700R4
Axle/Gears: Posi 9 bolt differential 3.27
Re: Deleted evap canister now tank line leaks gas!

Appreciate the feedback guys,
Old 12-19-2014, 10:06 AM
  #12  
Member

 
darbysan's Avatar
 
Join Date: Jul 2006
Location: Las Vegas
Posts: 306
Likes: 0
Received 1 Like on 1 Post
Car: 1985 El Camino Choo Choo
Engine: L31 Crate 350 w/ TPI
Transmission: GN 200-4r
Axle/Gears: GN 8.5 3.73
Re: Deleted evap canister now tank line leaks gas!

TPI's were designed to have the gas tank run at 2 psi positive pressure. I think this was to help the pump. There is a check valve in the vent line just before the Charcoal Canister, which opens only when the pressure exceeds 2 psi. You should be getting only fumes through that line, so the idea of the other relief valve being plugged is a viable one.

I would re-install it if at all possible. It is a safety issue being removed. Remember, it is gasoline vapors that explode, not liquid. Using it causes no loss in performance, and in fact returns the gas vapors to the intake ( increasing mileage (infinitesimally).
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
1992 Trans Am
History / Originality
27
05-10-2023 07:19 PM
Infested
Tech / General Engine
3
05-22-2018 11:56 PM
AkDrifted
Engine/Drivetrain/Suspension Parts for Sale
6
08-17-2015 07:45 PM
wayshegoes
Tech / General Engine
8
08-17-2015 12:00 PM
actionj
Carburetors
4
08-16-2015 09:51 AM


Thread Tools
Search this Thread
Quick Reply: Deleted evap canister now tank line leaks gas!



All times are GMT -5. The time now is 07:41 AM.