I've had a P0441 DTC w/Check Engine light come on intermittently over the past 6 months on this vehicle. I've replaced the fuel cap and the purge control valve, but the problem still exists sometimes. After I replaced the purge control valve, the light and code stayed off for almost 2 months, but just appeared again. It always happens after a long drive that is followed immediately by a period of idling (like slow traffic on the Chicago freeways). It never happens soon after a cold startup. I've checked all the hoses I can in the engine compartment, and all seem good.

I've heard the leak detection pump could be a cause of this DTC. However, I would think the code would set on a cold start, not after driving an extended time period followed by an idle period that usually triggers the check engine light to come on.

Can anyone offer any advise so I can get this issue resolved?

Thanks for the reply. I did check the purge valve by disconnecting the line coming from the fuel tank, and when the purge valve operates, a vacuum is pulled on the inlet, but when the valve does not operated (as when the engine is idling and it stops clicking), no vacuum is pulled. So, I think the purge control valve is operating properly.