bubbabud

As i said before the hose inside the hose it is a preformed part specific to the year and model truck. you can remove it without droping the tank the best way ive found is to unbolt the bed and lift it off just remove the screws around the filler necks and unplug the light harness. the fillers wil stay on the tanks. You can then remove clamps and pull the hoses off and see whats blocking them

TheUglyTruck

So I got access to the vent valve on the top of the tank that goes to the charcoal canister. I took it out and it looks alright, I shook it and the little plastic valve in it shakes around. Kinda sounds like a PCV valve. Is it supposed to be like that? I've never messed with one before, I was just wondering.

DaDubba

Any updates on the EVAP blockage? I have a 2006 5.4 with the larger 35.7 tank. It will not fill without clicking off fuel pump and takes like 20 minutes. Been doing this since I bought it a year ago.

rbrais

Good chance there is some rot in the vent. Check the filler neck and the top of the tank. My father just had this problem on his '04 silverado. Had to drop the tank and swap out the inlet to the tank.

nauss85

having a few of the same issues with mine. I use my rear tank all the time. My gauge doesnt register the rear tank until it has about 1/4 tank. Gauge reads above Full in front tank. I know for a fact the front is full because I shook the crap out of the truck and could hear it sloshing around. I think my pump and sending unit are both bad in the front tank and sending unit in the rear.

89f150billy

I have an 89 f150 and I had to buy a front tank when I got the truck, when I got it I noticed that the filler hole, were the hose conects to the tank, had tthe big hole like normal and then inside that hole it a smaller hole that I guess the inside tumbe was sapose to go in. The inside tube wouldn't fit in it so I just didn't worry about it and I put the tank in, when I tried to fill it up it did exactly like ur saying. If I ever get time ill ccut it out and see what happens, have your tanks been replaced?

5Rangers

Its probably full of gas already because the DFR is bypassing gas from the rear tank. Also in front low pressure pump is probably junk. So. Let's review:
DFR bypassing
front low pressure... shot
front sender ...shot
rear sender ...shot

#1 problem with our trucks... fuel supply system..

DaDubba

RBAIS - thanks for the tip. I figured we need to get in there and check all the vents/tubes and possibly that canister. Just wondering how common of a problem this is on the 2006. I know this particular truck spent a lot of times in off-road and dusty/dirty conditions; so its likely something is blocked.

rbrais

I wouldn't think dust and dirt would be an issue with the vent, since the system is sealed. Rot is the main issue, which is typically associated with snow areas or ocean areas. Cheap steel from China and salt are a bad combination.

SeanAA

I have a 1989 and have had the same issue. When you drilled your holes, did you remove anything, or just drill it right there. If you removed it, I suspect you may have corrected a kink in the hose when you put it back in. I was really disappointed that this didn't work for the OP.

I have to find the oldest gas pumps I can because they seem to have a less sensitive shut-off, but still I can barely put in a gallon every few minutes. I thought I found the problem when I had to replace the midship gas tank pump. When I removed the tank, I found the inner rubber fill tube cut off where it connects to the metal filler tube. I replaced it with an uncut one from a parts truck and no fix. It was really hard to feed back into the outer vent tube so I put a light coat of synthetic grease on it and wiped as much off as possible so it wouldn't get in the tank. So, I'm as sure as I can be that I didn't kink it, but not positive. When I was done, I wiggled the inner tube around and it seemed to be free of any binding. My vapor valve is really old, but it seems to work fine and I don't think there is any way this could cause it to get backed up. It just let's the vapor out when pressure builds up, mainly from heat, I think.