i swapped a 2nd gen jdm b16a into my 93 si coupe last year, ever since then i have had my CEL come on after driving for 5 or 10 minutes, something like that. i've checked the code with the diagnostic port and its a code 23, a knock sensor, i've checked the knock sensor connection. i've checked for breaks in the wiring. but found nothing. from what i do know, when the knock sensor is throwing codes VTEC is supposed not to engage but mine does. i've never had any problems with that. i can hear it quite clearly. thats the part that confuses me the most. i've tried resetting my ecu, unhooked the battery, taken out the ecu fuses, let it sit, hooked it all back up and let it run. checked the ecu for codes and the code is gone. until i drive again for a little bit, then it comes back. it doesn't happen if the car just sits there and idles, only after driving. its been confusing the hell out of me for a year and i just wanna get it dealt with. any help at all would be appreciated.

 

Are you sure you wired the knock sensor right? I had the same problem and VTEC engaged fine so thats not really strange ( I think).

Or maybe you just need a new knock sensor

 

how would i go about making sure its wired up right? i know the wire goes to the right place and goes to the right slot on the ecu, other than that what else is there to do?