Hope this is the right section... Well, I swapped a B16 into this kids CRX. It's been running good since the day I put it in back in August. He wanted me to pull the head 2 weeks ago so he can send it to go get ported and to get a valve job. Anyway, we get the head back, I put it back on (new head gasket, new intake and exhaust manifold gaskets, new head bolts) and the Vtec won't turn on and rev limit is at 7500k I went over everything, including the wiring, 5 times and it still acts the same. The car runs fine, doesn't misfire or anything, it's just no Vtec and early redline like I said earlier. I try my ECU (it's chipped with a REAL Mugen program) in his car and Vtec turns on and the rev limit is fine, doesn't cut out early. So I take off the Vtec Solenoid and Pressure Switch, clean it up, and it still acts the same way when we use the a Virgin PR3 or PW0 but still runs fine with my chipped PR3. Any ideas? No Codes , no nothing. Since it works with my ECU I looked at all the things(and wiring) my ECU bypass'... like the o2 sensor, the knock, and Vtec pressure switch. If all else fails he said he would send his ECU out and get chipped but I know that just band aids the problem, not fix it. I threw his ECU into my car and it runs fine so it's not any of the ECU's we got.