My 03 Forester XS started to have the same problems.I bought the filler cap at the Suburu
Dealer. After talking to the parts guy, he asked me if i filled my tank up while the engine was
still running. Well i told him i sometimes do....but only when im in a hurry...then he asked if i
topped off my fuel tank??? He asked me if i ever took the time to read over my owners
manual...i told him no!!! He told me im not the only person to not take the time to read it. He
told me to look up filling the tank. Damn me...if u look in that section it plainly says, DO NOT
FILL YOUR TANK WHILE ENGINE IS RUNNING OR DO NOT TOP OFF YOUR TANK. It
seems your charcoal fuel canisters get flooded with raw fuel. Subarus are very touchy about
that.Your check engine light will immediatly come on in both instants. Of course it will cancel
the check engine light out its self out. Only after the extra fuel in the canisters are depleated
out of the fuel emission system. Take the time to at least look at the manual.
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