I have a 94 civic d16z6 and my vtec dont kick in and my rev limiter is coming on at 6500 rpm so was just wondering if someone could answer me if this was an ECU problem

 

Is your check engine light on ?
If so, check your codes & get back to us.

 

no CEL

 

What is the exact model of the ecu? 37820-p28-a01 ?

 

A02

 

Does the car get up to operating temperature?

 

yes it does

 

I would suggest probing the vtec signal wire for 12 volts while performing a street test to see if the ecu is sending 12 volts to the vtec solenoid.

My guess is that you are not "feeling" vtec & thinking it isn't working when it actually is.

 

this is not my first honda nor first single cam vtec its not a matter of feeling it i can t even here the motor speed up and then that would not explain why my rev limiter is coming on at 6500 instead of 7200 like it should

 

Still it is a good idea to test for 12v from the ecu to the vtec solenoid while driving. Just have a friend sit in there with a test light or voltmeter.

I have seen stock tachs be off that far, so who knows.