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16826 EVAP Emission Control Sys: Small leak
P 0442-35-10 Intermittent

1) Your gas cap is loose.

2) The seal at the gas cap is bad.

3) The seal at the fuel sending unit is bad. It is accessible through the top of the trunk, and their are instructions here or on Audipages. It is a fairly common problem.

Reset, and see if it recurs.

If it is num 3, see if you had a recall done on it.
it came out a out a year+ ago. If you did not see the dealer, you would not have it done.
DM