P0441 evap code fixed

[DaveB]

My daughters Jeep has had the infamous P0441 for several years now and this year they wouldn't let it slide for the emissions test. Could have had something to do with my erasing the code too soon before the test. This code can be any number of things from a bad gas cap seal, leaky fittings, bad purge valve or computer. I did find a loose vacuum fitting and fixed it but that wasn't enough. Another part that can cause a problem is the evap purge solenoid. The computer drives the solenoid directly via a switched ground wire. The computer will only switch it on and off once the system is in closed loop mode. When the solenoid is working properly you can feel or hear it turn on and off. The purge solenoid opens up and allows engine vacuum to pull vapors from the charcoal canister into the intake manifold. The purge valve on my daughters Jeep was never switching on. I checked the solenoid resistance and and the wiring to the computer it all checked out good so my worry was that the drive circuit in the computer was bad. I removed the valve and tested the solenoid by applying voltage directly to the solenoid. It didn't switch. I tried my spare solenoid and it did switch. While I was playing with the parts I noticed that the purge solenoid has an "up" position on it. The one in my daughter's Jeep was upside down. I'm not sure if running it upside down made it stick in the closed position but that is how it was stuck. I put the spare part in and after the Jeep came up to temperature the valve started switching as it should. I cleared the error code and we have been driving it around and so far no check engine light.