I have a 97' civic ex coupe and I was wondering at what rpm range does the vtec kick in? Also what are the other components that need to be workin before the vtec kicks in.

 

I have a D16Z6 and I start to hear the crossover whine at 4980 to 5100 depends on how fast you are going. Your car is a d16y8, correct and i think they are very similar if not almost the same so i would say the same time should kick in.

In order to work i believe you need good enough oil pressure along with temperature. and the obvious such as vtec solenoid working, sensors.. etc

 

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