Hyundai Repair: Small Emission Leak, hyundai elantra gls, hyundai elantra

Question
Regarding my 2000 hyundai elantra gls with 2.0 engine.  The check engine light came on - was told it was a small emission leak - changed gas cap - didn't work. dealer recommended fuel injector cleaning - didn't work.  Purge valve was changed - didn't work - now they are saying have to replace charcoal canister.  Please advise what could be wrong before i replace all the emission parts.

Thanks !

Answer
If you've got a code for a small evap leak, there's no way the injector cleaning could cause the problem.  On this particular vehicle, it's also impossible that it could be the purge valve because of the way the system tests itself.

The canister is a possibility.  But so are several other things.  The problem could be with the fuel tank or anywhere the vapor control system behind the purge control valve.  The way to be sure is to have the vehicle diagnosed-- i.e. someone locates the actual leak.  

For this problem, I'd primarily recommend taking the car to the dealer.  The dealer's scan tool has the capability of commanding the evaporative system self-test to run, so the dealer can monitor the current state of the system and isolate different parts of the system during testing to narrow the possible sources of the leak.  To my knowledge, generic scan tools don't provide the capability to command the self-test to run, and the nondealer shops have no way of verifying the vehicle has been fixed after repairs.  I'd also recommend going back to the dealer that has (presumably) made the diagnoses and (politely) demand that they determine what's wrong with your car and verify that it's actually repaired before charging you any more money and before returning your vehicle to you.  In fact, if they recommended all the repairs solely to address a small evap leak, then I think they owe you a refund for the purge valve and the injector cleaning.

If you cannot get satisfaction out of this dealer, take your car to another.  On principle, you should avoid rewarding their incompetence with more opportunities to have more of your money.  If there are no other dealers nearby, you can also try calling Hyundai's customer assistance number, but I'm not sure they'll be able to provide any significant assistance since your car is outside the warranty period.