Oil where?
 

Oil on the outside is caused by the valve covers not tightened down enough I get that all the time. Its more prevelent towards the back of the engine than the front. Scince you have the throttle body off when changing the plugs its a good idea to check the valve covers. If the plugs are oil fouled on the inside where they fire than the rings could be weak or valve seals could be leaking. Beefing up the ignition to a multiple spark type might help burn the oil better but it won't cure an ailing engine.
The problem with the Toyota head design is the spark plugs are right in the middle and anything that gets trapped up there be it water oil or sand it stays there.

more than likely your valve covers are leaking and when you pulled the plugs the oil just went down them
try cleaning them up and restarting the car
when you say the car doesn't rev well... does it surge when you try to gas it?
does the car smoke out the exhaust?
the temp sensor it is complaining about would be the ecu temp which is a green two pin plug on the side of the thermostat housing, check out the wires & plug and make sure they are fine

let us know how you go from there :)

the reving issue is that when i first start it it runs and idles fine. after it warms up for 5 to 10 minutes it rev up and down up to 3000 rpms about three four times than if its in nuetral(5 speed) itll just shutter ffor a few seconds and than dies. when you got to start it again it wont. itll turn over just not start. if you wait 10 to 20 minutes she'll start again and do it all over again. i changed the O2 sensor that did nothing. could it be my fuel pressure regulator or injectors?? if any ideas let me know.
thanks

Ive got the leaking oil thing too, I Think the pcv thing is leaking thou, cause its really oily sometimes. As for the odd rev, have you checked for major vaccum leaks, like the intake hoses coming off or something? Also look under the hood, And see if that vaccum thing that is next to the idle screw isnt doing it. BTW, what does that thing do? (the thing with the filter) I plugged mine into a vaccum line, And now when i left off the gas it doesnt annoyingly stay revved for a second. But it didnt really seem to change anything else.

I'm having the same problems with my crx. I think it may be the fuel pump on the crx but am stumped. I think the person who can figure out your problem can also shed some light on my problem as well.If you figure out what is going on let me know:)

is there any way to test the fuel pressure regulator???? I just removed it thinking that might be the problem but want to know if you can test it before i spend a $100 on a new one

i once blew the valve cover gasket and that caused the car to run like crap only on 3 or 4 cylinders. there was oil all over the spark plugs and it filled the holes up like an ice tray i just cleaned the oil out with a vaccum and replaced the plugs and gasket and then it ran fine.