can any one please tell me where the service connecter in a 91 prelude is.
See if the drawing at page 3, right hand side, at the link below helps: http://media.honda.co.uk/car/owner/media/manuals/PreludeManual/62sf100/5-17.pdf
Do you want to adjust the ignition timing, or read error codes? If the former, the 2-pin Service Check connector is behind the top of the passenger-side kick panel, just ahead of the door, and under the dash. It's blue or gray. If the latter, see page 15, here: http://www.tegger.com/hondafaq/misc/3173_ICCR_E_14JAN03.pdf