how to tell if evap vent VALVE IS BAD
on 2002 Hyundai Sonata

removed from canister but unable to get movement when battery applied

3 answers 3 comments
I use a scanner and select 'functional test' from the evap menu....What code(s) did you have?
Well if you are testing it correctly and it isn't working, the writing is on the wall. :-)
Not sure if I am testing it correctly. I applied battery power to the terminals and nothing. I think I read somewhere that if you could blow through the tube without resistance, it was ok. I know that some valves need to have pressure applied to the vent to trigger the solenoid.
That valve works on a vacuum system, no pressure assist needed for operation, where's your ground?
Other bit of info to find out (I don't have Hyundai technical info handy) is , if it's a 12 volt or 5 volt signal. If you apply 12 volts and it's designed for a low voltage signal , then you will fry it right then.
That's good information, it's 12v on this, computer grnd. Thanks Bro. Hope he didn't put 12v to the ground, ooops