The factory check valves are odd in that the inlet is a different size than the outlet, which means an aftermarket replacement requires replacing all the hoses too. In my particular car, the hoses need replacement anyway, but that doesn't solve the issue of the fittings at the far end. Finding a universal check valve that happens to have the correct, different sized fittings on it seems like a challenge, and ill-fitting hoses are probably not a cure to an evap leak code. :)

FWIW, the hose+valve assembly is $90 at the dealer. Not free, but not horrifically expensive (unless you consider it's $90 of rubber & plastic). But the original stuff lasted 130,000 (plus or minus) so I don't feel too bad about the cost. Besides, I will be elated if a $90 part fixes the damning CEL on a $750 Volvo. Heh.

I did find someone somewhere claim that S40s have the same check valve closer to the fuel tank, and it's part number 1275226. That's $16, but I couldn't find out for sure whether it's the same check valve or not. I'll see if maybe the dealer has one in stock when I pick up the $90 hose assembly, and if it is if they'll let me weasel out of the special order. ;)

Reminds me: I did peer under the car to see how the rest of the system is doing, and found a short rubber coupler between a plastic line and a little doohickey by the filter is obliterated, so that needs to be fixed too. Anyone know what that doohickey is or does? Has an inlet in the bottom and an outlet at the top, but that's it. Maybe a damper, another check valve, or?

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