1996 Evaporative Emissions System

[ericv1984]

I think I asked this before on here but I can't remember if I did or not, so, sorry if I have before but.... Could a faulty or bad downstream oxygen sensor be throwing a CEL for a Evaporative Emissions System? Wasn't sure if the oxygen sensor was even part of the emissions system but on www.rockauto.com, they're listed under "emissions", so I'm starting to think that maybe they are.

The CEL for the Evaporative Emissions System comes on and then goes off about a week or so later so I'm going to be changing my downstream oxygen sensor tomorrow.

 

[Zimgxp]

It is part of emissions, it controls the air fuel mixture. All that O2 sensor does is monitor the converter effiency. You have a problem with the evap. system. What is the code?

 

[ericv1984]

It is part of emissions, it controls the air fuel mixture. All that O2 sensor does is monitor the converter effiency. You have a problem with the evap. system. What is the code?

P0440. Already changed the gas cap and fuel filter. I already know the possible solutions, but wanted to know about the sensor first.

On http://www.obd-codes.com/p0440 it says "check/and or replace the sensor", are they referring to the oxygen sensor?

 

[blebs]

Are the lines rusty underneath the car? My wifes Cavalier has a leak somewhere in the canister purge line and it throws that code off every now and then. I thought it was her gas cap because it sure doesn't feel like it's fitting tight at all.

They are NOT refering to the O2 sensor. They are talking about the charcoal canister purge sensor and that, I'm unsure of it's location. I think you have a line leak somewhere.