PR4 ECU 91 Civic LS swap Code 21

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New Member
I've got a 91 civic hatch with a DA integra motor and a 91 integra LS OBD-0 PR4 ECU. I'm getting a code 21, but when I looked it up it said code 21 is VTEC Spool, but I don't have VTEC. Could the wires just be hooked up and shorting out or something, because the guy before me had a B16A in it? Any help? Thanks.