Intake port grime, gasket oil normal?

[ihaveavibe]

Folks,

Wondering whether some nasty looking residue on the intake is normal and what looks like oil around the gasket surface.
Also tips on how to clean it and would need fixing would be welcome. I took the manifold off and the photos show (poorly) what I see.

Details:
-2003 base Vibe, around 95k mi.
-Notice rough idle, poor fuel economy especially in cold (13mpg-17mpg).
-Nasty smelling exhaust on cold start, guessing partly unburnt fuel.
- Used daily for several short trips (0.5 - 1 mi) of late with a few longer ones weekly (15mi-60mi) (patterm since around 70k miles).
- I am in the process of cleaning the throttle body and took off the intake manifold. I'm changing the thermostat (in case poor fuel economy is due to stuck open). I've already changed the PCV, spark plugs, cleaned MAF, swapped air filter in the last 2 or 3 years (this has been going on for a while).
- There are no error codes.

At this point i'm guessing it might be running rich (not getting to closed loop) and/or poor combustion.. I've looked at short term and long term trim but I don't recall anything out of the ordinary, however my expertise is severly limited (none). I've looked at the O2 sensor performance.. might be slow but again, not sure (and no codes).

My main concern is not so much the soot (though I'd like to clean it) but the rough idle, smelly exhaust on start, bad mgp and any lurking issues.

Thanks for all help!

[zbyers]

The soot could be normal if the vehicle does a lot of short drives.

Cleaning the things you mentioned, and doing a basic tuneup should help with the fuel economy and rough idle.

[ihaveavibe]

Any suggestions for what to clean with? I was going to use throttle body cleaner and a paper towel. Or maybe a tooth brush... i suspect it will drip down/in.

Also, is the oil on the gasket a concern? How did it even get there?

thanks