I recently started getting a check engine light for the following code:
P0447 Evap Emission Control System Vent Control Valve Circuit Open
I can clear the code, drive for 30 miles and eventually the code will come back on. It is even more of a problem if I clear the code, go for a short few miles drive, stop, turn off the car, and the check engine light will appear.
From some research, I heard that the canister close valve could be the culprit. This is the valve on the right rear underside of the car, attached to the charcoal canister. I replaced the valve with the same exact part # from a known good valve and I have the exact same problem.

What's next? I am not sure what other areas to look at? Any specific diagnostic I can do with a multimeter or something else?
Thank you, C.J.

 

Any tips?

 

The ECM is not 'seeing' a complete electrical circuit for the CCV.
I assume you are talking about the 1999 XJ8?????

Here is the DTC guide

bob gauff