Rep Power: 0

I recently flushed the radiator, replaced plugs with platinum 2 plugs, changed air filter, oil and filter, and pcv valve. I had cil for o2 sensor. So I changed it and solved the problem. Took a 300 mile trip all highway cil came back on , then 2 days later went out and now I am having a stutter in acceleration on the second start and trip out, but no problems when I first start and go to work. If I stop at a store and start back up that's when I have the problem. Plus idle seems to run high in park and low at red lights almost low enough to stall?????

 
Rep Power: 813

change to ngk plugs, they work better. and try cleaning the throttle body and idle air sensors around it.