I have a 92' civic hatch with a 95' LS motor and a p28 wiring harness. The car starts, but it redlines at 3000 RPM in neutral and in drive. The vacuum hoses are all connected, what could be the problem? Also, the car idles at 3000 RPM.

 

Sounds like your using an auto ecu. Check to see if ur ecu is an auto. That would explain why you cant go past 3k rpm.