Engine runs rough after fuel filling

[Srh]

09 outback xt,
The last 2 times I have filled up with fuel, engine has rough idle, stalls couple of times.
No check engine light logged.
Any ideas

 

[bmart]

Water in fuel is a very likely suspect.

 

[DragonWagon]

09 outback xt,
The last 2 times I have filled up with fuel, engine has rough idle, stalls couple of times.
No check engine light logged.
Any ideas

is it when you first try to start it after filling? sounds like a plugged evap canister. they can clog naturally or can get filled with fuel if you keep trying to fill it after the pump clicks off the first time. either replace or pull the hose off the back of the canister just to test to see if thats the issue

 

[Dick Foster]

Water in fuel is a very likely suspect.

Often happens when a service stations' tanks are almost empty. Crap accumulates over time from condensation, dirt, etc.

 

[Mr Practical]

Often happens when a service stations' tanks are almost empty. Crap accumulates over time from condensation, dirt, etc.

I had always heard this as well but it is incorrect. Each pump has a filter that separates particulates and water from the fuel as it it is pumped from the tank. Sometimes when you fill up the pump seems to run slowly. The reason it is filling slowly is that the filter is clogged and needs to be changed. Imagine my astonishment that after 40 years I found that the words my Grandfather spoke to me (about gas tanks) were untrue.

The problem sounds like a stuck roll over valve enabling the tank to be overfilled. When overfilled the vapor return line gets gas in it which then clogs the evap canister. The solution? Stop over filling the tank or have the rollover valve replaced. I had a car with a similar problem yet we drove it for 10 years using only the "don't top off the tank" rule.