snyderiii

All,

About 2 years ago I had my fuel tank replaced. Within a week or two i blew my 3.0 and subsequently did a 3.4L swap.

Here's my issue: First, when i open the gas cap there is a significant amount of pressure. I know it's supposed to be like that to a degree, but sometimes i almost cant get the cap off. Second, when I'm filling the truck up it almost ALWAY overflows from the gas neck. Unless I'm filling it at about the bare minimum speed some amount of fuel is going to burp out. But... i also get a 0460 regularly.

Now, I have done quite a bit of troubleshooting with PCV valves, et al (using ORS Mike's knowledge) and I'm about 99% sure they are connected correctly (both electrical and vacuum).

Is it possible all this is related to the vent hose which goes from the tank to the charcoal cannister? I also got a "new" cannister from the junk yard and that same issues have been occuring so i figure that isn't the problem.

Looking for advice/info on this?

Also, where on the gas tank is the vent hose connected? Is there some kind of "vent" in the filler neck that could be fouled and causing these issues?

Thanks,
Bill

scope103

I would guess something is wrong with the tank; you shouldn't be able to get fuel to overflow from the filler neck ever (with the slight possibility you're filling it from a pump with a broken shut-off -- try a different pump next time). That would have nothing to do with the EVAP system as the cap is off.

You might have the lines to the canister reversed, but if you're starting with a "new" ("junk") canister you'll need to at least test it. http://personal.utulsa.edu/~nathan-b...76evaporat.pdf

snyderiii

Roger. Just so I'm being clear, when fuel burps out of the filler neck, the tank isn't actually "full." If I wait for a few seconds, there is actually room to put another half a gallon or sometimes a whole gallon into the truck. And it's definitely not the pump, because it's happened at almost every pump at every station throughout almost every fill up since i got the swap done (last July). So if there is the "something wrong with the tank," where should I look first? Is this possibly whats causing my evap system to throw codes as well? I can take it back to the place that put the tank in, but they are probably going to be annoyed that it took this long for me to gripe about it.

scope103

I've never taken a tank out, but as I look at the drawing http://personal.utulsa.edu/~nathan-b...91fueltank.pdf it looks like the purpose of the "No. 1 fuel hose" is to prevent the burping you describe. Clogged? Broken? Missing? The line to the EVAP canister isn't nearly big enough to vent air from the tank while it's being filled, so those aren't connected.

I'm not aware of any "codes" thrown by the EVAP system. I also don't know what you mean when you say you get a 0460.

wyoming9

iTrader: (1)

The 3.4 does throw Evap codes but this P0460 must be a typo.

I gotta say your vent hose is blocked. Might be a pain to remove it and clean every thing out.

Then if your area has high speed pumps I could see it being possible I always use the slowest speed possible.

You did go with the Evap system for the year 3.4 you have??