Need vacuum line diagram for 2002 Park Ave due to code P0440
http://www.obd-codes.com/p0440 -- check this out for possible solutions. Also your vacuum hose diagram should on a sticker either attached to underside of hood or alone the front rail of engine compartment.
Did you put a factory cap or factory replacement back on or a new generic cap. Most older vehicles require a vented cap. Newer vehicles with emissions need a sealed cap, the tank is vented through the vapor system. If the car can draw air through the cap it thinks there is not one there!
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