Hi, I'm new to this site so please excuse me if this subject has been covered. I tried searching for the issue but have not been able to find anything.

I have a 2005 Altima 3.5 SE. A few months ago I noticed the following symptoms.

1. When I let off the gas to slow down for a traffic light the RPM will remain around 1200 Rpm until the car comes to a complete stop. Then the idle will drop to normal idle rpm.
2. Due to the higher rpm stated above the rpm spikes as the transmission downshifts to lower gears. For example, I let of the gas and the RPM will drop to 1200 rpm. The transmission will shift down and the rpm spikes. It's acting like I'm still pushing on the throttle while down shifting. I've also seen the rpm drop to 1000 then spike back up immediately to 1500 right after a let off the throttle.
3. If I accelerate just enough to go in to second gear and let off the throttle, the car will maintain 1200 rpm until I apply the brake to slow the car down almost to a complete stop. Then the idle will drop. It's almost acting like it's cold all of the time but what's throwing me off is that the idle drops when the car is stopped.

Any help on this is appreciated.

Thanks

IACV probably. Try a relearn first.