Problem With Evap System On 2000 Elantra Gls Options

[vgoel80]

Check engine light on my 2000 Elantra goes ON & OFF periodically. It seems that it goes OFF after I have drive for some time after re-feuling the car or when the feul tank is close to empty. I read the OBD error codes twice and it came out differently both times, first time it was P0441 & P0134, second time it was P0134 & P0722. I would like to know whats wrong before going to a mechanic, any help would be really appreciated. Also, emission check for my car is due in another couple of weeks, will the car pass the emission test if I remove the fuel tank cap periodically to keep the check engine light OFF? Thanks in advance.

[jsinton]

You describe a bunch of problems, all unrelated.

P0441 - Purge valve, incorrect flow. You probably need a new purge valve. They tend to knock around under the hood and get toasted. Later ones had insulating foam around them to protect against getting beat up. You might be able to fix it by taking it off and cleaning it with carb cleaner and lubing it with WD40.

P0134 - Oxygen sensor, no signal. You need a new O2 sensor. It's the one that screws into the exhaust manifold.

P0722 - Output speed sensor, no signal. The speed sensor on the output flange of the transmission is giving a fault. Probably needs a new one.

You can't pass emissions by leaving the gas cap off. They tend to read codes nowadays. You might be able to clear the codes, drive around for a while to reset the ECM and pass.