[Rouele]

Hey all you subaru experts!

I have a minor issue here that started a week ago. I was embarking on a road trip and topped up my fuel tank. When I started my car, it took a few seconds of turning to start then it stalled. After a couple of shots, it started but was sputtering for a few seconds until I gave a little gas and put it into gear to drive off.

This happened to me every time I filled my gas tank to full on the trip. Stalls a couple of times before I can actually get it going. Funny thing is, it starts fine and does not stall when its under full, half tank or even on almost empty.

Any idea as to what could be happening? Thanks!

 

[happyforester]

Is your check engine light on?

I had a similar issue with a few years back with a different car... Infiniti G20.

Whenever I topped-off the fuel to "really" full, meaning after the pump automatically shut off - I gave the nozzle one more blip, the car would have a hard time starting, fuel pickup seemed off (like it was a pressure issue), and the check engine light would turn on. The light would stay on until I had gone about 10-20 miles, shut the car off completely, and then restarted it.

The mechanic I took the car to said it had to do with the fuel overflow "catch can" filling up with too much fuel. This in turn would cause an electrical warning to the computer that there was something wrong with the fuel delivery and cause strange things to happen. The next time I filled up with gas, I didn't do the blip after the pump automatically shut off and the car didn't have the problem again.

I can't say your issue is the same thing, but it's just a thought.

 

[themathguy]

Maybe warm engine the problem?

I have a thought that maybe the problem isn't the full tank, but starting on a warm engine. I once had a car that started fine cold, but struggled a bit on warm starts (had to give it extra gas).

I'm thinking, every time you filled up with gas, the car probably wasn't off for more than a couple minutes. But perhaps any other time you stopped and turned the engine off, it was for maybe 15 minutes or more? (Enough to let the engine cool just enough to make a difference)

To test this, when you get to a destination and can spare a few minutes, turn the engine off and wait the amount of time it takes to fill up, then try starting again.

 

[themathguy]

Full tank or process of filling

I thought of something else you could try to eliminate possible causes.

I wonder if it's not the full tank, per say, but instead the filling process (I don't know, maybe fumes confusing the EPA sensors, and the ECU changes something?). You could try stopping a gallon or two short of full (i.e. estimate it) and see if it still happens.

I don't know if this suggestion has any validity or not, but it might be something I might try to try and understand the real problem.

Remember, you can waste a lot of time trying to solve a problem if you don't know what the real problem is. Just trying to help :icon_wink:.

 

[Rouele]

Thanks for the responses!

I tried not filling up the gas tank full but to 3/4 quarters tank and it still gave me the same problem. I was also talking with another Subaru owner and he mentioned that it can have something to do with pulling in sediment from the reserve tanks while fueling over the years, thus when im filling the car, the gas being poured in is just churning all the sediment, enough to choke the gas.

He also suggested changing the fuel filter, draining the gas thank and replacing the sock. This sound familiar?

 

[funkymonkey1002]

It also be the charcoal canister i believe.