05 aveo ls sputters when starts and rpms went to 4000 when i turned ac off

[roach_clip]

so to start after i changed the oil and spark plugs on my car i got a check engine light. i got it checked and it was a o2 sensor, the first one. i havent changed it yet (dont know where to get it) but when i start my car after about 15sec it starts to die and have a rough idle for about 20sec then goes to normal. thats pretty much every time i start it. on my way home today tho i started it and it seemed to take alittle longer and alittle rougher but then it was fine. when i was driving tho i decided to turn off the a/c at a light while idling and the RPMs shot up to 4000. but when i turn the a/c back on it goes back down to normal. so i tested all the way home and it did it everytime. when i got home i turned it off and back on and it didnt do it again. im just worried its somethan bad. maybe somethan with the throttle body. any help would be much appreciated. thanks

[petrified.rabbit]

that sounds like a bad o2, go to advance/pepboys/napa and get a new one.

[roach_clip]

how hard is it to do one of those universal ones where you do the wiring?

[petrified.rabbit]

if you can complete 4 wires connections of cut wires, you could do it.

[roach_clip]

what about the camshaft position sensor that threw up signs a long time ago but never came back. whats weird was it was right after i changed the oil and spark plugs.

[petrified.rabbit]

cam position sensor should not increase rpm. it will cut timing change spark..

map or maf, o2, and ait control fueling (2009+ have a maf and o2) you have the map ait and o2, which is idle speeds rpm etc.. even a vacuum leak will make it surge, but not to 4000 rpm. A vacuum leak to the map sensor will make it not get more fuel.

IF you had a o2 code already, and still have fuel surging issues, it is most likely the o2.

The cam position sensor code could have occurred if you fill the head with oil faster than it will run down to the oil pan, it would need to be run while the head still has too much oil in it though..