Have Mercedes Questions? Ask a Mechanic for Answers ASAP
Hello, my name is***** and i will do my best to assist you.I am going over your story now and will reply back soon with some info,thanks!
sorry i took so long, i wont be on too much today, ill chat with you later about this issue.
ok so i am not sure if we are on the same page any more, the fuel sender has nothing to do with the fuel filling nozzle shutting off. so do you know if replacing the sender helped the fuel level gauge at all?
did the code go away for the sending unit?
as for the charcoal canister and the fuel system, it has to be one of the 2 canisters.
the purge valve in the engine bay has nothing to do with the system. just the canisters because it looks like your model does not have a canister vent valve that i can find.
this fuel system is really hard to get some solid info on, if i was near the car it would be easier lol.
You dont have to do both, only on a later model they updated the sending units so you needed to do them together. not on yours from what i recall., ill look at the parts catalog again for the fuel tank.
lets stick with one issue at a time, if we jump back and forth it will take longer to figure out what is happening.
so lets stick with the fuel filling issue since that is a pain for anyone to deal with. sorry i have not been on as much, very hectic right now for me.
i pulled up the parts catalog earlier and found a check valve in line with the canister under the car. not sure where it located but its something that may have a effect. ill be back on in the am.
i will opt out at the moment and come back if there are no other responses. sorry i am not able to be on as much as i would like at the moment.
Generally when you see a problem like this it is your charcoal canister for the evaporative emissions systems. When you fill your tank, the gas going in pushes air out. It should go out through a vent valve, through your charcoal canister, which absorbs the gas fumes and allows filtered air back out into the atmospherre. When your charcoal canister gets clogged (usually from topping up the tank repeatedly, but sometimes from a faulty gas pump) the air instead tries to push back up the filler neck against the gas coming in, shutting off the pump from the sensor at the nozzle.
Have you checked the pins at the connector to the cluster- make sure they are not spread and are able to get good contact at all times. If the cluster is changed, and the fuel sending unit, that only leaves the wiring- but since you can get it to change by unplugging it, it would seem that it MAY be isolated to the connector.
I would just start out by inspecting it- if necessary to repair, you can get new wire ends that plug into the connector, and splice them farther back into the harness with heat shrink butt connectors.
You would have to get these replacement wires from the dealership. The ETKA parts film will allow them to look at the cluster, this will tell them what connector is on the backside, and what wire ends go with it. There are hundreds of different wire ends in the VW/Audi system, and different thicknesses of wire as well, from half a millimeter up to 5mm.
Sorry, I meant Mercedes-
If you have a new sender, and a new cluster, wiring is the only link between them.