5.0 with a lot of pressure in the gas tank..

tjustin_moser · 09-18-2001, 01:33 PM

I hae had a lot of trouble with my tank getting a lot of pressure in it. I have changed out the perge valve and my gas cap but I don't know what else it would be. I've called around but not too many people know what else the problem would be. It's a 91 GT without mods (for right now) I've only had it for a month. This is the only problem I have had and I would like to fix it.

302 LX Eric · 09-18-2001, 05:16 PM

It could be that your collection canister is blocked somehow. Basically, there is a tube that runs from the tank to this little black canister that is located in the engine compartment on the passenger side near the smog pump. If this tube gets blocked, then pressure will build up in the tank. The tube to the canister serves as a "vent." Inside the canister is charcoal (I think) which reacts with the gas fumes somehow.

As you can see, I know little about how the whole process works, but hopefully someone more knowledgable can chime-in on this one.

I do, however, know that if you block the tube you will get pressure build up because I did when I blocked mine. I had to block the tube with a screw because I ditched all of the emissions stuff (smog pump, et al) on my coupe.

Hope this helps. Good luck.
E

------------------
1991 5.0 LX Coupe - 38,000 miles

13.17 @ 106.14 mph w/ 2.138 60'

tjustin_moser · 09-19-2001, 08:18 AM

thanks for the help. I did check the canister but I couldn't tell if it was blocked or if it was the hose from the tank. what would the best way to unclogg the hose if that is what the problem is?

Phantom5oh · 09-19-2001, 09:40 AM

If that is the problem then you can clear out the tube by taking it off the car and blowing it out with compressed air, or you could replace the whole tube.

Phantom

------------------
CHECK OUT MY MODS

http://www.mustangworks.com/cgi-bin/...splay.cgi?1350

Loose Cannon Racing
Scarzi Machine Works

2FastLX · 09-19-2001, 10:47 AM

Let me know if you find out that's what it is. I have the same problem ever since the fuel pump install, and I checked to see if we pinched a line but they seem to be free with nothing clamping down on them.

Eric, If you just follow that line from the old charcoal canister back to the fenderwell and cut it and tuck it away inside the fender there's no need to plug it up.

------------------
Gunning for 12's!

Buy your parts here
ICQ# 42269241

302 LX Eric · 09-19-2001, 11:43 AM

2FastLX - what will happen to the vapors? Won't I have a strong smell of gas in my garage when my car just sits there in storage? Will the gas evaporate?

Thanks, E

09-20-2001, 01:40 PM

I had a problem like that when I installed a 255 intank pump with a new fuel filter. The gauge will go past max when I get on it or after a constant loong cruise (3hr trip to Houston averaging 80-90mph). Turned out the Autozone brand filter was defective and I replaced it with a Ford unit and that was the end of the gauge problems and the smell of gas as well.

------------------
Black SN95
TFS heads, Holley intake, AFM B-2 cam,
12.9 @110mph best ET
13.06 @111mph best MPH After gutting out clogged cats and a much better tune. Took Nitrous out for warranty work

didn't have time to put back in for track.

09-18-2001, 01:33 PM	#1
tjustin_moser Registered Member Join Date: Sep 2001 Location: Las Vegas, NV, USA Posts: 18	5.0 with a lot of pressure in the gas tank.. I hae had a lot of trouble with my tank getting a lot of pressure in it. I have changed out the perge valve and my gas cap but I don't know what else it would be. I've called around but not too many people know what else the problem would be. It's a 91 GT without mods (for right now) I've only had it for a month. This is the only problem I have had and I would like to fix it.

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09-18-2001, 05:16 PM	#2
302 LX Eric or '331 LX Eric' Join Date: Jan 1999 Location: Columbus, Ohio Posts: 2,142	It could be that your collection canister is blocked somehow. Basically, there is a tube that runs from the tank to this little black canister that is located in the engine compartment on the passenger side near the smog pump. If this tube gets blocked, then pressure will build up in the tank. The tube to the canister serves as a "vent." Inside the canister is charcoal (I think) which reacts with the gas fumes somehow. As you can see, I know little about how the whole process works, but hopefully someone more knowledgable can chime-in on this one. I do, however, know that if you block the tube you will get pressure build up because I did when I blocked mine. I had to block the tube with a screw because I ditched all of the emissions stuff (smog pump, et al) on my coupe. Hope this helps. Good luck. E ------------------ 1991 5.0 LX Coupe - 38,000 miles 13.17 @ 106.14 mph w/ 2.138 60'

09-19-2001, 08:18 AM	#3
tjustin_moser Registered Member Join Date: Sep 2001 Location: Las Vegas, NV, USA Posts: 18	thanks for the help. I did check the canister but I couldn't tell if it was blocked or if it was the hose from the tank. what would the best way to unclogg the hose if that is what the problem is?

09-19-2001, 09:40 AM	#4
Phantom5oh Registered Member Join Date: Mar 2000 Location: Boston, MA Posts: 334	If that is the problem then you can clear out the tube by taking it off the car and blowing it out with compressed air, or you could replace the whole tube. Phantom ------------------ CHECK OUT MY MODS http://www.mustangworks.com/cgi-bin/...splay.cgi?1350 Loose Cannon Racing Scarzi Machine Works

09-19-2001, 10:47 AM	#5
2FastLX The Photoshop Guru Join Date: Feb 2001 Location: Mecca, Indiana Posts: 1,419	Let me know if you find out that's what it is. I have the same problem ever since the fuel pump install, and I checked to see if we pinched a line but they seem to be free with nothing clamping down on them. Eric, If you just follow that line from the old charcoal canister back to the fenderwell and cut it and tuck it away inside the fender there's no need to plug it up. ------------------ Gunning for 12's! Buy your parts here ICQ# 42269241

09-19-2001, 11:43 AM	#6
302 LX Eric or '331 LX Eric' Join Date: Jan 1999 Location: Columbus, Ohio Posts: 2,142	2FastLX - what will happen to the vapors? Won't I have a strong smell of gas in my garage when my car just sits there in storage? Will the gas evaporate? Thanks, E

09-20-2001, 01:40 PM	#7
blkrain Guest Posts: n/a	I had a problem like that when I installed a 255 intank pump with a new fuel filter. The gauge will go past max when I get on it or after a constant loong cruise (3hr trip to Houston averaging 80-90mph). Turned out the Autozone brand filter was defective and I replaced it with a Ford unit and that was the end of the gauge problems and the smell of gas as well. ------------------ Black SN95 TFS heads, Holley intake, AFM B-2 cam, 12.9 @110mph best ET 13.06 @111mph best MPH After gutting out clogged cats and a much better tune. Took Nitrous out for warranty work didn't have time to put back in for track.