HELP? Smoke coming from motor...???

Hey, all.

2002 WRX Wagon. Recently serviced (~2 weeks ago).

I was on a commute, driving quite normally, and noticed a small amount of smoke puffing out from my hood scoop.

I pulled over, opened the hood, and the area around (what I believe to be) the upper exhaust cover was putting out a little bit of smoke. Here's a pic: It was the red/brown stained area under the cover that I guessed was the source.

The amount of smoke was very small, and it the smoke stopped completely when I opened the hood.

I'd not been driving at super-high RPMs.

I let it cool a bit, then continued on (driving very gently, barely touching the turbo), and the symptom did not repeat.

I called the dealer, and they said to check my fluid levels - cooland and oil were fine. They asked if the motor had been overheating - but the main temp gauge was no higher than normal. It hovers at just under the halfway mark along its whole range.

Later, when I got home, I popped the hood, and the whole area under the hood felt considerably warmer than normal.

Now: it *is* warm out these days. I thought maybe ambient temperature might be playing a factor.

Any other obvious things I can factor in here?

What's the best advice? Keep driving normally until the symptom repeats, or get it in to the shop ASAP regardless?

Thanks for all tips...

BD