I am helping co-worker with VTEC problem on 93 Civic. This engine he just put in and is a double overhead cam engine with VTEC. He says engine comes in 95 Del Sol but he got from Japan with computer and all. The VTEC comes in early at 3500 rpm and causes engine to load up or bog down. After 5000 rpm it clears up. We checked the solenoid and it is being turn on at that rpm by the computer, and should not come on till higher rpm from what we know. We have not found info to tell us what the computer is using to turn this on. Also his rev limiter is coming on to soon for this engine. Does anyone have more info on the system and what parameters the computer is looking at and so on. We have only found trouble code repairs for VETC on solenoid and oil switch but not on if system is not on right rpm. We tried Mitchell and All Data manuals on linebut no help. We are thinking he may have gotten wrong computer. The original computer for car does the same thing and it had VTEC
Ray