I just put a D15B SOHC Vtec in my '92 Civic HB; it came stock w/ a standard D15. I have everything done and I'm driving him now. My car drives well and the turbo kit rocks! My question is this, why won't my check engine light not turn off? I have the Vtec hooked up, however, I"m running a P08 ECU. To my understanding, the Vtec ECU is the P28. Because of this, the guys at the local speed shop hooked my Vtec directly up to my Greddy Emanage. Any help would be most appreciative. Thanks a lot!

 

https://www.hondacivicforum.com/m_208634/tm.htm
i posted this awhile ago, it will answer your ecu question...
yes, a p28 is a vtec ecu.. so is the po8 your using, and both are obd1, so your light might just be telling you your vtec is not wired,
it just stays on? all the time? no blinking, nothing?

 

I have my Vtec wired up...had a speed shop do it, because I'm not good at wiring. The light stays on permanently. Thanks for your reply I really appreciate it!

 

the vtec wiring is very simple, check the top section of the ecu section, i have a diagram there. i understand you have the vtec wired up, however you bypassed your ecu (which is a perfectly good ecu for vtec) tio do so, if all the systems the ecu is programed for are not functioning it will light up the cel, thats what its for... obd = On Board Diagnostics, if you local shop said your p08 ecu was not correct to run vtec they were mistaken

 

The P08 ecu is the correct ecu for that engine and does look for vtec. You need not go back to that shop if they dont know and simply dont look up the correct info on your ecu.

 

how come it took me so many words to say that??? (refering to marty's statement)

 

Thank you so much for this information. Im going to pass it along to my brother-in-law. I don't know anything about wiring. He's going to do that for me. I really appreciate your guys' help.