Hi
Does it ?

I feel my car is better (in terms of jumpiness )at morning (when RPMs at idle are 850~) than when it comes to normal (550-600) ?
(neglect the temp. factor....same temp at 9 am and 11 am)
Sorry if it was discussed before

 

the reason you probibly feel its better is because the engine is cooler vs after its all warmed up, and your car generally makes more power when the engines cool

 

...no.

Are you referring to a cold start versus a warm start? Not ambient temperature, that's irrelevant; engine temperature.

It's running a lot richer when it's cold and warming up, that may be the 'jumpiness' you feel (though 'jumpiness' is almost always a bad thing, not a sign of any 'performance' increase).

 

sorry ... I meant by "jumpiness" the acceleration........maybe wrong term I used.........