Maxima Forums - View Single Post - MAINTENANCE and MECHANICAL Information- Don't Post Questions Here! (UPDATED)

scrubnick · 06-29-2007, 01:16 PM

The P0440 is a generic EVAP system leak. The P1448 is a manufacturer specific code for the charcoal canister vent valve stuck open. The charcoal canister is located behind the left rear tire. It's a largish black box with a few hoses running to it.

First, check all of these hoses to make sure none or torn or otherwise damaged. If they check out, disconnect these hoses and the electrical connection with a pair of pliers. Then, remove the three screws that hold the box to the car, then push the rear bracket out of the way to remove it. With the box out, take off the two screws that hold the purge valve to the box. It takes a bit of force to remove the valve even with the screws out. Be firm, but don't break it.

Next, take some brake cleaner and spray through one of the holes so it flows out the other. Hose it for a good 10 seconds or so, then spray some silicone spray through it to lubricate it. Install the valve back on the box, put the box back in the car and reconnect the hoses and wire connector.

With the car back together, clear the codes on the ECU and you should be good. If this doesn't work, double check all the lines in that area and if all else fails, you might need a new canister vent valve. You should be able to test the valve by applying 12 volts to the two terminals. A replacement valve runs about $120 from a dealer, so do your best to fix your old one first.

06-29-2007, 01:16 PM	#57
scrubnick Newbie - Just Registered Join Date: Aug 2006 Location: Ypsilanti, MI iTrader: (0) Posts: 8	CEL: P0440 and/or P1448 DTC's The P0440 is a generic EVAP system leak. The P1448 is a manufacturer specific code for the charcoal canister vent valve stuck open. The charcoal canister is located behind the left rear tire. It's a largish black box with a few hoses running to it. First, check all of these hoses to make sure none or torn or otherwise damaged. If they check out, disconnect these hoses and the electrical connection with a pair of pliers. Then, remove the three screws that hold the box to the car, then push the rear bracket out of the way to remove it. With the box out, take off the two screws that hold the purge valve to the box. It takes a bit of force to remove the valve even with the screws out. Be firm, but don't break it. Next, take some brake cleaner and spray through one of the holes so it flows out the other. Hose it for a good 10 seconds or so, then spray some silicone spray through it to lubricate it. Install the valve back on the box, put the box back in the car and reconnect the hoses and wire connector. With the car back together, clear the codes on the ECU and you should be good. If this doesn't work, double check all the lines in that area and if all else fails, you might need a new canister vent valve. You should be able to test the valve by applying 12 volts to the two terminals. A replacement valve runs about $120 from a dealer, so do your best to fix your old one first.