ludicious

Okay, so I put a SOHC VTEC 93 Civic motor in my HF. Swapped out the HF ECU for an Si. Runs decent, still haven't got the ECU upgraded for VTEC... too busy with the Teg.
My problem... when the car is cold it runs like a scolded dog. Occasionally once it gets warmed up, it just looses all power. And I keep getting a Check Engine light, flashing O2 Sensor on the ECU. I put new O2 sensor in, no go... The only thing I can think is that my A/F ratio is off? Ugh, anyone else have this problem?

92CivicSiR

first of all, the Si ECU does control the VTEC because the D16Z6 motor is a SOHC VTEC motor, as far as the other problem goes, I would say check your ignitor, that is the only problem I ever had out of my 92 Si is the ignitor. call a parts store for that piece, they will either call it the ignitor, or the ignition control module, one of the two. I might be wrong, it could be something else, just trying to hlp though.

91sifreak

I had the same issue when i put my d16z6 in my car. I did all the same replaced the o2 sensor and then re-wired it and still got the same issue. So i traced all the wiring out of the ecu and the ecu ground wiring that connected to the starter bracket wasn't properly connect to the bracket. once it was reconnected the check lights went away. something else to try anyway.

Fast Attack Hatchback

ludicious

Yeah, I know the Si ECU doesn't control the VTEC... I'm considering HONDATA or ZDYNE for that fix. It's 320... but just a VTEC controller would cost me close to that. And they customize your fuel curve too.

Tanks 91Sifreek, I'll check my grounds. Your talking about the little multi-wire connector attached to the "L" bracket above the starter correct? I know the one by my clutch was a little lose when I first dropped the motor in... LOTS OF SPARKS! Quickly fixed that one though.
Thanks guys.