I just recently replaced my old f22b Vtec(140 000 Miles) with a newer F22b Vtec(25 000 miles), But theres a couple problems with it, if you rev the engine to approximately 2500 rpm you can hear a klonking noise as the engine rev's higher. I not sure but it may be affecting my Vtec because that's not working either. could it be my timing or somin else??

 

that knocking noise means ur engine is "knocking" or "pinging" ur air/fuel mixture is igniting before TDC this is caused by low octane or bad timing

 

Along with the above it could also be your valves, but at 25K those shouldn't be loose unless they have never had an adjustment.

I would check your oil levels, check your oil pressure, check your timing, and also check your valves.

 

the knocking noise isn't that loud, but i can slightly feel it rumbling while i drive, so if my timing is even off by a bit does it really do that and would that affect my Vtec to not work?