2000 Legacy Wagon Fueling and Idling Issues

[mcclish.lucas]

Hi All,

I've had an idling issue for awhile, and recently a fueling issue has come about and I'm wondering if the two are related.

I've had a shaky idle that has come and gone in intensity. The first time, I replaced the spark plugs and cables and the problem essentially disappeared for a week or two. The next time it popped up I replaced the fuel filter, PCV valve, and a broken crank case breather hose and the issue dramatically improved. Additionally, I've sprayed off my MAF sensor and checked my vacuum hoses for leaks throughout the process, but this led to no improvement in the condition.

Recently (within the past month or two) I've started having issues fueling. The fuel pump will shut off after a few seconds of fueling and continue to do so throughout my time fueling. After I finish fueling (I watch how much I'm putting in to make sure I don't overfill with the shutoff not being reliable), my car will often have a harder start.

I'm not sure if the two are related or not, but I wanted to get a second opinion before I started throwing down money on parts that may not fix the problem. I think these may be the possibilities:

1. The fuel filter neck/gas tank vent valve needs replaced. My thoughts with this is that the venting valve is not properly functioning

2. The carbon filter or tubing leading to the carbon filter is blocked.

3. The evap control solenoid needs replaced. I read an error code for this a few months before the fueling issue developed. I cleared the code after replacing the fuel filter, PCV valve, and breather hose and the code has not returned. It's a pricey part ($100), so I don't want to just replace it for troubleshooting purposes.

4. The idle air control valve (if this fixes the idle issue then I would assume the fueling issue and idling issue would not be related).

Thanks for your time and Suby wisdom!

[3Pin]

Are you getting any codes from the computer?

 

[montana tom]

#1,2 and three are a strong possibility.  The IAC valve normally does not cause a miss but causes the car to idle excessively fast  until thoroughly warmed up.

#3 seems most likely considering the code you did have. Also your fueling troubles.   Check rock auto price on the evap valve.

#2 is possible and much more expensive than the evap valve. Removing the  carbon filter and weighing it can tell you if it needs replaced.

#1 in Seattle I doubt you have a rust thru issue , its the easiest one to check.

Do you have starting, idling, rough running  issues immediately after fueling ? 

[montana tom]

Purge control valve , under the hood. Disconnect and see  if you can blow thru it.    You shouldn't be able to. (EDIT) look at the under hood picture to locate purge valve.

Edited June 11, 2018 by montana tom

[montana tom]

The evap system is no doubt causing your fueling and starting issues.   As far as your intermittent shaking. On a 2000 outback have the valves been adjusted ... ever .. since you owned it ?  Your shaking could easily be a valve tightening up as it heats up. Valve adjustment / valve cover removal on a subi is not for a novice, but it is doable if you have mechanical ability. 

[1 Lucky Texan]

coupla odd ideas - try fueling with hoses pulled from the charcoal canister - one at a time, might lead to where a blocage is.

 

(Flooded charcoal can or insect/mud nests, sometimes there's a cable going to a solenoid on the can - cable gets lose or is bad, etc.)

 

 

did you change a front axle? On automatics, you can sometimes feel vibrations when stopped in Drive, if the vibration stops when you slip into N, that can be due to a rebuilt axle.

[mcclish.lucas]

Thanks for the replies.

I haven't had the CEL turn on so I haven't checked for code.

I forgot to mention that it's a manual. I unhooked one of the hoses today while fueling and it actually solved the fueling problem! It was the hose farthest in from the right side of the car. If this diagram I found is correct (http://glasairproject.com/GlasairI/soobdocs/EG(H4)EVAP.gif, in my attached photo it's the hose on the bottom of the picture without the clamp), then I believe the hose I disconnected is the one that connects to the solenoid, and thus would affirm that it's most likely the solenoid causing the issue. I'll try disconnecting and blowing through it before I pull the trigger on a new one. Looks like they run between $80-$100 on Rock Auto.

I'm hoping/praying it's not the valves... To my knowledge, they have never been adjusted.

I'll probably get to replacing it early next week and give you all an update. Thanks for the help!

[montana tom]

The evap solenoid and the purge valve are two different parts, both part of the evap system .You found the solenoid its the likely reason for fuel filling issues.  The purge valve is under the hood and if you can blow thru it , then that's your hard starting after fueling.   As far as the shaking goes I doubt the evap system is involved at all.

[montana tom]

After you get your fueling issues corrected, IF you still have the shaking problem.  When the car is fully warmed up and shaking , Do a compression test. Much easier than pulling a valve cover. (if you own or can borrow a compression tester)  A tight valve will drop compression readings on that cylinder.  If you find a low cylinder, that is the valve cover to remove and check valve adjustment. (Of course if one is tight you must check them all)  If you find a tight one and your lucky the valve won't be burnt and your car will be back to 100%  (for an 18 year old car)