Originally Posted by TNtech
Coupe or Sedan?
440 General Evap System Failure
441 Purge System Performance
You have a HUGE leak somewhere, the NVLD pump itself is not working or one of the Purge Solenoid hoses is off. My bet is the canister line from the purge valve is split somewhere. You get those 2 codes when the PCM can't initiate the EVAP test.
Check also and make sure the purge valve hoses are not switched around backwards.
Sedan. What I can see underneath the hood looks good.
What's strange is that it seems to alternate between 440 and 441.. and sometimes, none at all... hardly ever both. Been seeing this code for quite some time now. That fact that it sometimes disappears on it's own makes me think it's the NVLD. I've read about this part having intermittent problems.