Dear Tom and Ray:
I was driving my 2007 Forester the other day when the check engine light came on (it has about 15,000 miles on it). I brought it in to the dealer, and they cleaned a spider web out of the charcoal canister hose. Does this sound right, or am I getting hosed?
Tom: Believe it or not, Mary, this is said to be a pretty common problem. I guess gasoline is the Chanel No. 5 of the arachnid world.
Ray: We've seen a number of service bulletins over the years alerting us to the dreaded spider-web-in-the-fuel-line problem. In your case, there probably was a bunch of webby stuff in the fresh-air intake line to the evaporative emissions canister. That was preventing the fuel tank from breathing properly (fresh air has to enter the gas tank to fill up the space left by the used gasoline; otherwise, the tank will slowly implode). That set off your check engine light.
Tom: So I don't think the dealer is hiding anything, or trying to cover up some other problem. I'd guess that he told you exactly what was wrong, and he fixed it.
Ray: Of course, in order to prevent this from happening again, he'll want to sell you the specially made Subaru Bird of Prey to eat any future little "line blockers."
(Car Talk is a nationally syndicated column by automotive experts (and brothers) Tom and Ray Magliozzi. Write to them at the Car Talk Web site.)