Hyundai Repair: 2001 elantra. Fault code # 0440, emission control system, evaporative emission control system

Question
Hi, hopefully you can help me.  My elantra has been repeatedly throwing the code: P0440 (I clear it, check the gas cap, and it comes back around 30 miles later).  My research says its an "evaporative emission control system malfunction".  Does this have to do anything with the air-filter from the evap cannister or is it a problem with the CCV?  Have you heard of any of these being a ongoing problem with the elantras (my friend's throws similar evap codes) and if so, do you have any suggestions on fixes?  If yes, how would I go about doing this?

Thanks for any advice.


dave

Answer
Any or all ov the above could be the problem. We usually go through a 15 page diagnostic procedure to narrow that and many other evap codes dowm. It requires special tools and a lot of patience. You could throw a ccv and filter at it and cross your fingers but past that there is quite a bit involved.