Use this to get future codes: http://www.actron.com/code_lookup.php

P0440 = EVAP Emission Control System Malfunction

From Volvospeed (JBVolvo):
The Do It Yourself Method

Check the hose running from the intake manifold, to the Purge Valve for any cracks, cuts, or breaks that may be causing a vacuum leak. If that's fine move on to step 1 and continue from there as necessary.

1 - first test the purge valve with a tester. You can't "guess" its ok. It either holds or doesnt.

2 - If you determine the Purge Valve is not at fault, follow the line from the Valve to the evap canister. Inspect this entire line for any signs of cracks or breaks. If it's not air-tight it'll cause a vacuum leak.

3 - If this line checks out fine, check the connection(s) at the EVAP canister. They can rot and crack or break also causing a vauum leak.

4 - If the connections check out fine, inspect the entire EVAP canister itself for cracks or breaks.

5 - If the canister checks out fine, follow the lines off the canister that run across in front of the engine and all the way back to the fuel tank. Inspect these entire lines for signs of cracks or leaks. (You will probably come upon whats known as a "roll-over valve" mounted just in front of the rear passenger wheel. It's a valve that stops flow if the car exceeds a certain angle. i.e. - in the case of a vehicle rollover....to cut fuel to the engine, and in an effort to prevent spillage) Check this valve, and its connections for leaks as well.

6 - If these lines check out fine, remove the access covers to the fuel pump and sending unit and check the connection of these hoses to the tank.

If none of this works for you, you can put a VERY VERY low psi through the system with a compressor and feel/listen for the leak source, but this isnt really recommended because you could cause more harm then good if you over pressurize it.

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My name is Klaus and I am a Volvoholic.