Hyundai Repair: purge and close valves, purge valve, numeric digits

Question
QUESTION: A couple of days ago the check engine light came on, so I went to the dealer and they told me that the purge and close valves need to be replace, $57 and $58 respectively but just the labor will be like $300, because they said that they have to remove the gas tank. I was looking on the Internet and i see that the purge valve is on the engine side and i figure the close valve must be on the tank. According to the people's experiences just by changing the purge valve might go away the problem. I think i can change the purge valve but the close valve inside the tank, i am not sure how to change it. I need advice. I also need to buy a electronic reader to reset the error, and i don't have one, i also need advise to which one to get.
thanks
Felix

ANSWER: Hi, Felix.  The purge valve is indeed located in the engine compartment and is typically easy to replace.  The location of the close valve varies by vehicle, so I'll need to know the year and model of your vehicle to advise you whether you'll reasonably be able to service it.  I can say that although, on some vehicles, it's necessary to remove or lower the fuel tank to access the valve, it is not *inside* the fuel tank.

It's also odd that a vehicle would need both the purge and close valves.  Unless you've two separate problems, I'm going to cast serious doubt on this diagnosis.

Did the dealer report to you or otherwise document the trouble code?  (They should have if you paid them for diagnosis).  If you can tell me the trouble code (Pxxxx where x's are numeric digits), I can do a better job of advising you on where the issue may potentially be.

You can reset the ECM by disconnecting the battery for 30 seconds.  If you're going to attempt to do your own repairs, a code reader may be a reasonable investment, but it's only necessary to read the codes, not to erase them.  Once again, if I know the year and model of your vehicle, I can tell you what features will be necessary for the code reader to work with your vehicle.

Do follow-up with the following information-- I can probably be of significantly more assistance:
1.  Year and model of vehicle.
2.  Diagnostic trouble codes, if you know what they are.

---------- FOLLOW-UP ----------

QUESTION: thank you expert it is 2001 4 door Hyundai elantra Gls 146000 miles
Today after work I started my car and the check engine light is off
Now I don't really know what to do, do you think it will come back?
Thanks

Answer
If the problem is still there, the lamp will come back on.  If it's gone, the lamp will stay out.

In general, for noncritical failures, it takes on each of two simultaneous self-tests to cause the lamp to come on.  If the test passes three consecutive times, the lamp will go out.  So, what we know at this point is that your problem is intermittent.  Is it possible you left the gas cap loose or installed it improperly and then corrected the cap later?

On the 2001 Elantra, the purge valve is readily accessible under the throttle body.  The close valve is somewhat readily accessible as well.  At the left rear of your car, there's a plastic housing which contains the canister, canister filter, and close valve.  It shouldn't be too hard for a do-it-yourselfer to remove the assembly, disconnecting the hoses and wiring attached to it, and then disassemble it to allow for the close valve replacement.  If you've done other work on your car yourself, you can probably replace these items as well.