Rep Power: 0

Hey this is my first time posting. I've looked all over and at different posts, threads and forums and haven't found much on this problem and nothing that helps.

Ok here is what happens, while driving, usally above 45 mph, I put the car in to neutral to come to a stop at a stop light and the rpms drop from 4500+ to 0 smoothly. Nothing rough, nothing like killing the engine. Sometimes but not all the time the engine idles low at around 500-700 rpm and thats the times when I can get it to die from going from high rpms to neutral. The rest of the time it is at 900 rpm as it has been since I got it.

The engine light was on and I fixed it, it was the #1 O2 sensor, I swapped it out and its been running smoother. I also cleaned the throttle body out. I also have an Injen CAI. I have had it to the shop to get diaganosed but they didn't tell me anything other than the compression is good and the spark plugs are good.

I really just need to know if this is a big issue.

Thank you for any assistance.

 
Rep Power: 519

do an idle relearn?