I HAVE A P0499 EVAP CODE CAN ANYONE OFFER A POSSIBLE SOLUTION OR AN IDEA OF POSSIBLE CAUSES

 

Well, check the first things first. Replace the gas cap, check the vacuum hoses running to and from the intake manifold and the charcoal box underneath the driver's side of the bed. It will be under/near the gas tank filler hose.

 

I have an 04 Dakota 3.7L that was giving me p0449 error. Problem ended up being a damaged wire coming from the NVLD. If you disconnect the wire harness at the NVLD there's three wires, mine were black, orange, and white with a green strip. When I measured the voltage between the orange and white with green (WWG) wires it was about 2v, I followed this wire upstream towards the front driver side tire where it plugged into another wire harness (only two wires go this far, the orange and wwg) and disconnected the wire harness and measured the voltage from the supply side, measured about 5.8 volts.

So I knew I had a bad connection, turned out to be the wire harness I had just disconnected. I cut both plug connectors off, (the two near the front tire) and used shrink wrap and butt connectors to splice the wires together then wrapped them with electrical tape and hung behind the plastic splash guard.

I went back to the wire harness at the NVLD and again checked the voltage between the orange and wwg wires, this time I had the 5.8v. Plugged everything back in and problem solved.

Best part is my radio reception and been really bad for a long time and fixing this also fixed my radio reception I'm assuming the broken wire was shorting something.

Hope this helps someone

 

has anyone seen working with the harness/NVLD fix a P0442 code?
mine comes on once every 6 months and then goes away on its own a couple of weeks later.