Burning plastic?

[MattB]

I noticed after refueling my 2001 I30 tonight and driving it home that when I got out of the car there was a faint smell kind of like burning plastic. It appeared to be coming from somewhere around the left rear wheel well. No smells or anything coming from the engine compartment or tailpipe. The car had a 90K service and intermediate exhaust recently and is in excellent mechanical condition. No leaks of any kind. The smell faded quickly after the car was parked. This is the second time this has happened, and both times the smell has occurred after I drove the car home from refueling it. Any ideas on a cause?