i have engine light on , again , it is tellin me a code of po 440 ? on 1999 Buick LeSabre

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ive been having problems with this car recently had simalar problems i have changed the silenoid purge v, and they also changed the fuel pump and fix some wires on the harnes, now i have this problem with this code? can someone help......
(2) Answers
(3) Comments
code po440 evaporative emissions control system malfunction....
evaporative emissions leak ....dont get nervious its just the gas cap check it to make sure the rubber seal around the cap is not dry-rotted..I would just replace the cap with a OEM cap from your local parts store in witch the code should go away on its own after a few opening and closings of the gas cap ....

hope this helps
If you decide to repair this have a shop perform a smok test to reveal leak.
It has been awhile!