Nissan Repair: Check Engine Light, charcoal canister, fact notice

Question
QUESTION: Hi Von,
My 01 Sentra SE just stored the code P-1448 Evap Canister Vent Control Valve Open and also the code P-0455  Large Leak Detected-Evap Control System.

I've been told that it is probably due to a problem with the gas cap and did in fact notice the problem after refilling the car.  I was just wondering if any of this sounds familiar to you.  I've cleared the code several times and made sure the cap was on tight and the light came back.  Please let me know what you think before I dive into this deeper.

Thanks,
Tim

ANSWER: Tim,

Could be the gas cap so resetr the code and make sure the cap is tight.  If not you either have a bad vent control valve on the charcoal canister or a hose that is loose or degraded that needs to be replaced.  But, first, I would reset the code and tighten the cap.  If it comes back start tracing vrom the canister back.

---------- FOLLOW-UP ----------

QUESTION: Thanks Von, I cleared the code and made sure that the cap was tight and got the damn light again.  It seems to come on when I'm down by a half of tank of gas.  Anyway, I going to have a look at the canister and hoses.  I believe the canister is located somewhere on the back of the car near the gas tank(can you confirm this).  I ordered the Chilton repair manual from the library for some help but would like to start on this project ASAP.  Anyway help/suggestions that you can offer will be greatly appreciated.  Thanks again.

Tim

Answer
Tim,

The caniser should be in the rear of the car, behind the wheel-well.  You should see the unit if you lay on the ground and look up.  There is a metal shield that will obscure your view.  Remember to check the hoses where the connect.  From front to rear they use hard lines.  But at the tank, canister and engine they connect with hoses and clamps.