All of a sudden my car sounds/drives perfect?

[BMAN_986]

So for a least 4-5 months of this year my car was making a funny high pitched sound on start up. It lasted about 30 seconds or so. I did some reading about it and it sounded like it was something to do with some kind of secondary air pump working on the cat to warm it up (I think I read about it on rennlist). I never got to record the sound even though I had been meaning to. The other thing that my car had always done was for the first minute or so of driving from cold it would be kind jerky if I moved up the gears quicky.

Then a couple weeks ago I went on a 7 day vacation out of the country and my car never got drove.

When I got back I started my car and the noise (on start up) had gone. It's now been 2 weeks and I have not heard the noise at all (it would happen twice a day without fail). Even the jerkyness seems to have gone.

I read somewhere before that after a number of days of non driving, something in the ECU resets and on next startup the car "resets" and readjusts to the ambiant environment.

I live up in Seattle. The weather has definetly got warmer after my vacation.

Am I smoking crack or did "something" happen to my car whilst I was away?