I let my car warm up today as I rummaged about inside, looking for my sunglasses. I didn't find them so I left it running and went inside to look for them. I usually don't let it warm up much before I take off, because I have enough driveway and slow road before I hit the highway to get it warm.
So after the extra warm-up time (didn't find the glasses) I came back out and noticed a new clicking sound from the front left engine bay area. I opened the hood to investigate, and felt the charcoal cannister assembly chattering, as if whatever switch or valve on the top of it was rapidly cycling. As I moved it, the clicking stopped. After I shut the hood the clicking started again for a few seconds and then stopped. Why is it doing that? And how much is this going to cost?
I have been getting a seemingly random code 26 since I have owned the car. And after I got home this evening I found my clip-on sunglasses, they were in my front shirt pocket.

There is a solenoid on top of the evap canister that can be replaced. I don't think its horribly expensive either.

If the solenoid is bad, then it would be an easy fix. If its not... then perhaps a vacuum leak? Too much vacuum? Its the canister purge solenoid, iirc.... hmm I'm kinda at a loss otherwise.

Yes, it was the solenoid that was chattering, as if it were switching on and off rapidly. I'm pretty sure it isn't supposed to do that.
I figured maybe someone else has had the same problem before and might know if the problem was in the solenoid, wiring, or the ECM.

Well I have a code 26 QDM, that isn't random, but not constant SES light. I also have a fuel smell when the car is just shut off [smells like a rich AFR, but generally smells like a carburated car idling]. Getting about 17mpg, and is slowly declining. Also this code has lasted thru two motors and two ECUs, and a different harness. And my canister is loose... so I'm interested in some insight fo' sho'.