Funnily enough I was going to make a thread similar to this a few weeks back. Going to give mine a service this weekend and clean the vtec solenoid see if it helps. Its almost like a restricted feeling.

 

[quote name='richmc' timestamp='1381907350' post='22829912']
The car won't VTEC till its up to temperature, if its just in general the ECU learns your driving style and adjusts fuelling accordingly. Pull the ECU fuse (or disconnect the battery if you have the radio code) for 5 mins put it back start up and let it go through two cooling fan cycles, then take it out for a good thrash, it will re-learn its fuelling and give you the VTEC beans back.

Intrigued by this - what are the implications of "ECU learns your driving style"? I drive sensibly on most commutes, but when not limited by traffic open up VTEC. What differences in response should I expect if I spend one week mainly pootling, one week mainly thrashing, with an ECU reset between each week?

 

Note to self - learn to quote correctly

 

Some clarifications...

ECU learns but only in partial throttle not in WOT, technically knock control is not learing in WOT.

So no adjustments in WOT. On a honda in WOT long term/short fuel trims are not applied.

Temperature is referenced in map and add's/removes fuel based on temperature.

A map sensor is used like in excel spreadsheet to reference load against revs etc and how much fuel to inject and how much timing to run in WOT, so if the map sensor was off or under readings etc it could cause bucking/hesitation in WOT and partial throttle as its not getting reference correctly thus not looking at correct cells and giving back duff readings.

You can change some of this though with a flashpro.

 

Is your car a pre or post facelift? Is it just sound you're going by? At what kind of speed do you notice this effect?

The reason I ask is because my post-facelift seemed to have a slipping clutch at times, more so above 70mph when driving in a 'spirited' manner and it felt like there was a lack of / loss of power. After much investigating and exercising the search function of this forum, I found it to be the Clutch Delay Valve (CDV), fitted to post-facelift cars. I had mine removed and it's made a world of difference. The car feels and sounds brutal at VTEC crossover every time.

 

None, because the statement is wrong. The ecu doesn't learn your 'driving style'.

What the Ecu does do is exactly what s2konroids has posted. But this has nothing to do with your driving style.