Is the gsr motor in a gsr, or is it swapped into something, I don't think you mentioned it h:. Did it run ok before you took the p28 out?

I don't know where the sensor is, but do download the helms manual for the 94 integra and you'll find it very helpful.

Here are a bunch of manuals:

http://www.hondahookup.com/manuals/

Heres the specific one you need:

Honda/Acura Integra (1994) Service Manual DB7, DB8,DC2,DC4 (37Mb PDF)

You need to sign up at the site, but its the same as when you signed up here. Hope that helps some...