How long for Reset ECU to kick in?

I read on an earlier post that I can reset the ECU by pulling the hazard fuse... is the change immediate or do I need to drive around for a while (and if so, for how long)?

I did notice an immediate difference in the rev limit - but are the other functions of the ECU also immediately updated?

after you pull the fuse, leave it out for 5 (?) seconds and after you put it back in, start the car, and let it idle for a few minutes (or more) so the ecu can get the proper readings and adjust accordingly.

will that work on my car. does the ecu adjust to my intake and exaust? will it mess anything up?
matt

yes, it should adjust for small things like increased airflow (like intake). You may not notice anything though, but it can't hurt anything.

to correctly reset the ecu:

remove ecu fuse for 5min then plug it back and start the car without touching brake or gas, let it run for 5min without doing anything, and the ecu will reset for the increased flow into and out of the engine as well as any other mods performed,