well depending on the modle vtec will normaly kick in anywere from 5,000 RPM's to 5,500 RPM's... u willl deff noticed a diffrent sound from your engine as it tends to sound a bit higher pitched in my experance... basic throw it in idel and slowly let it rev up, u should hear the diffrence, if ya don't well then eather you model car does not have Vtec or you vtec is not working
You could just pop the hood and rev the car with the throttle body and have your finger on the vtec selanoid and when you rev up past a certain rpm the selanoid should click, if you feel it click then vtec is engaging.
And mine deff did hit vtec in neutral it was a y7 block with a d15b head and a d15b ecu and it would hit vtec sitting still and my friend had a 1990 hatch with an obd0 ecu and it would hit vtec in park.
geez, ok vtec will only engage if its warmed up enough,if you have enough oil pressure, if the solenoid is good and pressure switch and if the ecu is good, you can hook it to a switch but that's still not true vtec because all that does is lock the cam it does nothing to the fuel maps like real vtec does.and also real vtec will only work after your going 20mph if you have a single cam sometimes you wont even hear it change over but on a dohc vtec motor you should be able to hear it change over depending on if its stock or tuned
I had the d15b with the obd1 computer and it did have vtec in neutral and yea vtec won't engage at all if the car isn't warmed up or if it doesn't have oil in it. "thats where i convinced my friend that my car was out of vtec fluid" haha. But i meant vtec was on a button not a switch, so he could be driving and push the button and vtec would engage you could tell that vtec engaged too it got faster but only if you hit it at the right time if you hit it to early the car would like bog down. I checked to make sure vtec worked on my car by simply reving it up and holding the vtec selanoid. did it on this kid's crx too i could actually hear that one clicking while i was reving it up tho.
just temporary install a light bulb on the solenoid , 12v is sent from the ECU to open the solenoid , the bulb will light up when vtec engages , this will tell you if ECU is opening or trying to open the solenoid
if you want to test the solenoid , just disconnect the connector in the solenoid and put 12v positive wire directly to the solenoid , it will clic if its fine , the car must be in ignition position with the car TURNED OFF.