Italian term (edited): - Leggera irregolarit� di erogazione in accelerazione

Hi Maria,
Basically as you give the engine more gas it will start to choke and feel like you’ve actually let out on the throttle. This can be caused by too rich a fuel-air mix (not enough air or too much fuel at any one throttle opening) or other things.
It feels like the engine hesitates instead of revving on. You’ll lose acceleration, and maybe top end power and speed too.

Other causes can be leaking manifolds, malfunctioning ignition systems, badly adjusted carburation and/or ignition timing, other ignition faults or fuel starvation.

More reference:
http://www.google.it/search?hl=it&client=firefox-a&rls=org.m...