Can't gas up at more than a trickle or pump shutdown
 

Guys,
The only issue I have been having with my car is when I try to fuel up, it's a 2003 CLK55AMG . It happened occasionally right after I picked it up 5 months ago but is now a constant issue.

When I try to fill the tank the pump shuts off like it will when the tank is full even when it is almost empty. I have to trickle the gas into the car and it even shuts off half the time then. It takes me forever to fill up. Any suggestions on what could be causing this? It doesn't matter what station I take it to and I've tried different positions with the pump handle.

Someone mentioned that there is a flap in the bottom of the fuel filler pipe to stop fuel coming back up the filler neck when cornering.

I think this is the issue since when filling up I can hear the fuel filling up the neck and then I have to wait a few seconds to add another little bit of fuel. is there a way to replace this without replacing the entire tank?

Thanks for the help in advance,
Bob

Most likely a problem with the charcoal cannister that traps vapors while filling.

Possibly someone had overfilled the tank & RAW fuel entered that cannister.

M.B. Doc,
Do you have a part number and diagram of where the filter is located? I've checked on a few different part sites and have been unable to find the charcoal filter.
I do hope that this is the problem since it should be much less costly than a new tank. It is driving me crazy, since I drive an average of 1,200 miles a week right now (waiting for the company car to come in) I'm filling up once a day and taking 15 to 20 minutes at the pump in 20 degree weather is driving me nuts!

Thanks for the help in advance,
Bob

Do you always use the same station? I bought gas at a local station lately, and when i stuck the nozzle in and pulled the trigget to lock it in at high flow, it tripped off, did that several times. After five minutes of playing I had barely 4 gallons in the tank. So I drove down the stree to another station and it filled up quickley. I tried two other stations other than my "usual" and at one other it would only let me trickle in. I used my nuclear brain to think about how the shut off works,a nd though maybe there was something in the filler that was causeing gas to back up in the filler. I played with it for a bit, and found that if I turned the nozzel 90 degrees clockwise, holding it to the left instead of straight down, it would let me fill up at high speed. My observation is, some pumps flow faster than others, and at higher flows it will back up in the filler neck, but if I rotate the nozzle about 90 degrees, it flows down the neck "better" and I can fill up at the higher speed.

Just my 2 cents, YMMV. Chuck

Chuck,
It happens at several locations. I had thought it might be the one station near me but it happened at a lot of stations and I've tried the nozzle in all kinds of positions and flow rates.

Thanks,
I appreciate the input.

Bob

I've never heard of this before, Bob. Be sure to let us know how this turns out.