need help troubleshooting engine issue (long)

[Aaron K]

Well, a couple days ago I was going to change the oil in the sr20, and upon
removing the oil fill cap, I saw vapors coming out and a very definate gas
smell.:( That can't be good... I have had poor gas milage for a while now
(about 20-22 mpg, mostly city driving and not lead footing it everywhere)
but I figured that was probably due to the O2 sensor. I have no idea how old
it is.

Here is what I know so far: About 6-8 months ago I had a compression and
leakdown test done, and it the compression was within spec (3 cylinders were
175 and one was 180) with no major leakdown problems. The cooling system
held pressure too. I have had issues with the car burning a lot of oil at
one point, about .5 quarts every 500-800 miles, but that seemed to stop on
its own. Also, the PCV system is working (new valve) and I can't see any
evidence of a leaky injector (I turned the ignition on with the spark plugs
removed and didn't see any gas pooling up on top of the pistons).

Not that its necessarily related, but I have the typical startup clatter
even if i let the car sit for just an hour or two. I remember feeling that
on most other peoples cars it only happened if it sat for several hours or
overnight. The reason I mention this is that twice before I have had some
startup-clatter-type noise only about 5x-10x as loud and just as temporary.
Scared the crap out of me, and I don't know what it was or what caused it.
The engine also has a new timing chain tensioner, and after pullling off the
valve cover tonight, it looks like everything is ok. The timing chain guides
seem like they are in good shape, and the tensioner plunger is extended.

Regarding the gas smell in the oil, could one or more of my valve guides or
seals be shot? Is there anyway I can really tell? What else would cause
this?

Oh, something else that struck me as odd: When I had the valve cover off,
the exhaust valve springs, the spring retainers, and the immediate area
seemed noticably darker and dirtier than the intake valves/springs. Is this
typical? (here is a picture:
http://www.luminus.cx/pics/unlinked/valvetrain.jpg)

I also pulled my intake off to look inside the throttle body. I cleaned it
before, but its all gummed up again, and I can also smell a hint of gas in
the oil gum left in the bottom of the intake manifold.

Does anyone with more experience with these engines have any idea what could
be causing this? Any help is greatly appreciated,

Aaron

(maybe its time to buy a sr20ve...)